I think a lot of atheistic objections to religion, like this jpg that you posted, are a reaction to a simple-minded concept of the Divine. Yes, many people do indeed think of Divinity as an all-powerful Man with a White Beard who has a bunch of rules, a bunch of demands, and a quick temper. But that vision does not fit with the more sublime and subtle Divinity that, for example, the deep spiritual mystics and sages throughout the millennia have talked about experiencing.
Simple-minded people who are uncomfortable thinking for themselves and are uncomfortable with ambiguity sometimes seek simple moral rules, and interpret the words of great beings (like Jesus, Moses, or Buddha) to signify simple rules (“fundamentalist interpretations”, as you say). Yes, clearly human history is full of examples of how that seems correlated with wars, inquisitions, and other such problems.
The deepest spiritual teachings that I have encountered (in, for example, Zen Buddhism or Advaita Hinduism) contradict such rules, and instead say that there is no absolute truth, no absolute morality, and no actual “right” and “wrong”. Still, in those traditions, moral behavior is seen as a fundamental building block for a spiritual practice in which one realizes and manifests the profoundest possibilities for human psychospiritual evolution. In Buddhism, for example, the traditional teaching is that vipassana and prajna (meditation that leads to seeing through the illusion of the world – for example, transcending the illusion of “absolute truth”) is built on a foundation of shamatha and Samadhi (meditation that concentrates the mind), and that shamatha is built on a foundation of sila (moral behavior) and good karma.
So, mature spiritual practice does not mean that “anything goes” in this life. I think that for sincere and realized Buddhists (and for sincere and realized beings who have cultivated themselves to other religious traditions), certain behaviors are discouraged and others encouraged for the same reason why trying to walk through an open door is encouraged over trying to walk through a wall – it just works better that way. In this view, moral religious prohibitions come from going with the weave of this universe we live in, in the same way stroking the fur of a cat in one direction works, and stroking a cat the opposite way simply doesn’t. Simply put, making a habit of injecting heroin, and shooting bullets at people that cut you off in traffic usually doesn’t lead to happiness for oneself or others, and refraining from doing those things is more likely to.
Immanuel Kant is famous for having formulated what he called the “categorical imperative“, or the idea that all people should follow the same universal rules of morality. Sixty years later, Søren Kierkegaard commented that some people (which he called “Knights of Faith“) have a sophistication, inner development, and clarity such that following the subtle, ever-changing dictates of their own conscience is a clearer and true-er guide to moral goodness than following societal rules. But, Kierkegaard warned, for the majority of us who are not quite as psychologically evolved as a Knight of Faith, simple categorical rules of behavior is probably going to be the best guide to helping us to be the best person that we can be.
You say that the “ideal is or should be to develop one’s own morals”, but I think that it is more accurate to say that “the ideal is or should be to cultivate oneself to be the kind of person for whom developing one’s own morals is more positive than following categorical imperatives”. Everyone wants to think of themselves as a Knight of Faith, as someone who can be moral beyond traditional rules. And, with all the psychotherapy, meditation, and other forms of psychospiritual growth in the modern word, perhaps many modern people are.
I think though that there are many people who believe themselves to be above traditional notions of morality, when what they are is just immoral. The first example off the top of my head: there is a syndrome of murderers (for example Eric Harris and Dylan Klebold at Columbine, Nathan Leopold and Richard Loeb in 1924) who have read Nietzsche, and consider themselves beyond “herd morality”. Also, it is my interpretation that, in the sixties, many kids threw off traditional rules around drugs, sex, and general obedience. As they grew up, however, most of them had a strong inner compasses, and they turned out as pro-social citizens. A fair number of people, however, took the same breakdown of traditional rules of morality, and turned it into the explosive growth of crime and addiction that occurred in low-income environments between 1965 and 1990. So – perhaps traditional simple categorical-imperative moral rules have their use after all.
[Violent crime rates in the United states per 100,000 population beginning in 1960. Source: Bureau of Justice Statistics]
A few random thoughts on morality:
[1.] From my perspective, looking across religions and secular philosophies, the simplest formulations of moral behavior for humans are - don't lie, don't steal, don't be addicted, and don't engage in violence for any reason except self-defense. It seems like, the perennial wisdom is, that's what works between people. Discussions of morality can get infinitely more complicated than that, of course, but that's it, in a nutshell.
I have personally found that doing my best to live by those four rules seems to correlate with happiness in me, and positivity in my relations with others.
[2.] You mentioned, "things that drain energy and/or aren't conducive to goals of enlightenment, community, self-respect, etc. but aren't directly harmful to others ..". I think however it is impossible to help or hurt oneself without simultaneously helping and hurting others. If a behavior is healthy (vitality creating, or growth experiencing) or hurtful (escapist, draining, etc) experience, to whatever extent it is either (or some combination of the two), then the impact is felt both by oneself and by everyone one interacts with. As the great spiritual teachers have said, distinctions like selfish and altruistic, self and other, inside and outside, free will and determinism, and life and death are mostly illusory - they exist mostly because we are not paying close attention.
I think that this is especially true concerning addictions. We tend to think of our addictions as private matters. As one of my Zen teachers said in a lecture I attended, however, "The greatest act of kindness that we can do for others is to give up our addictions."
[3.] You say, "Christopher Hitchens argued effectively in his book "God Is Not Great" that the religious ideals of people like Ghandi and MLK who have profoundly and positively influenced belief and behavior for the better weren't necessary to achieve their goals, i.e., that secular morality alone can promote greater awareness, justice, kindness, etc."
To my mind, yes, as you seem to be saying Hitchens was saying, many modern people often are moral people by just referencing the phenomenological secular worlds of philosophy, politics, economics, empirical science, etc. But to my mind, being moral in that way is more difficult than if one also has a tangible sense of the mystery of Eternity. It's kind of like making plans for a house rebuilding without stepping outside the indoors of a house onto its surrounding property - possible, but, again, notably harder.
[4.] When the word "morality" is used in American political life, it is often used to refer to sex for the sake of pleasure rather than procreation (specifically, homosexuality, abortion, contraception, pre-marital sex, extra-martial sex, porn, polyamory, and perhaps we could say, divorce too). Sometimes it is used more broadly to refer to not just sexual pleasure, but other forms of worldly pleasure (drugs, alcohol, music, television, movies, fashion, hot tubs, etc). It seems to me that the biggest reason why people I socialize with don't like the word "morality" is because it makes them think of fundamentalists telling them that they shouldn't/can't do those fun things.
I can certainly understand why so many Bay Area alternative/burner type people would be repulsed by this formulation of morality. But I also understand why fundamentalists make it.
In university, I had a professor of myth and religion explain that that there are two primary movements to the human soul. One of them is the "ascending"/"transcendental", where the Divinity/reality/the good is outside of this world. With this motion, our job is to deny the body so as to escape up and out of this world to rejoin the True World of Oneness beyond. In this view, God might reach in to inspire a holy text or part a sea every once in a while, but Divinity is basically a cosmic watchmaker who made the world and is now outside of it. Unbalanced examples of this might be traditional or fundamentalist Christian, Muslim, or Jewish monotheism, Platonic Gnosticism, Thai forest Buddhism, or some schools of fundamentalist Hinduism.
The other motion is "descending"/"immanent", where Divinity/the Real/the Good is down here in this world (or could potentially be, with effort), and nowhere else. Examples of this include paganism/"wicca"/nature worship, tantric sexual paths/hedonism/love of pleasure, some forms of Taoism and Shintoism, money-hungry materialism, and Marxist or socialist materialism.
If we are imbalanced towards the first, ascending direction, we will claim that pleasure is sinful - since pleasure is the main thing that keeps us lost in this world of illusion and away from union with the One. If we are imbalanced towards the second path, however, then pleasure often seems to be an irremovable simple part of our humanity, attempts to do without it seem superstitious and emotionally cold, pleasure sometimes becomes the most important thing to us, and we will get angry if anyone asks us to do without having as much as we want of it.
My professor of religion said that the most mature spiritual paths are those with a balance, the simultaneous rising up and sinking down, realizing that the imminent and the transcendent are both Divine - the dreamer (God/Goddess) is the dreaming (Time/Change/Action) is the dream (World). In Mahayana Buddhism, this balance is captured in the popular saying, "Form is emptiness, and emptiness is form". I personally am inspired the image of a tree simultaneously growing branches up to the sun, and roots down into the Earth.
From a place of balance, I think we can see that pleasure has its place, and so does letting go of pleasure for higher ideals. Neither is an absolute simple value, and both have their place.