Classical Greece was just one of my examples. My main point is that, even if all documented groups had spirituality and religious practices (which I don't refute), is that you have not convinced me of the cause and effect between morality and spirituality in human society.

1. I do believe people did not need a modern formal education or a ton of free time to reflect and think at a high level. If that belief is an issue, then we fundamentally disagree on that point.

2. You continue to state that all societies have documented spiritual and religious practices, and I apologize that I didn't make it clear enough that I understood you meant all societies and that I was only using a few societies as an example, but you have not stated why that means spirituality caused morality or needed to have caused morality. Genuinely, could you explain to me how it is implausible that any moral principals found in those religions were the product of societal morals of the time and not the other way around? Even if morals are subjective, religious interpretation is also subjective. As far as meanins to humans and structure goes, neither is more objective than the other in my opinion. Or maybe morals are more objective if we assume they were developed as guided by survival of the species rather than as guided by religion.

3. If you want to ignore everything else, here's as simple a summary of my question as possible: Why do you insist religion -> morals? Why can it not be morals -> religion?