I think you are erroneously assuming that your experiences are universal. Do you really think that no one would prefer destructive pleasure over eudaimonia? Hedonism has been documented thousands of years ago in the context of traditional, heroic societies that are vastly superior to anything merely biologistic that history has known. If that could not prevent hedonism, why do you think that people will naturally avoid it if you restore some form illiberal tribalism?

In my opinion, the reason why you seek to define and pursue some form of higher life for yourself is precisely because you have internalised spiritual principles despite your rejection of Christian and pagan theologies. Pursuing these principles is not a given for most people. Your second paragraph essentially confirms the voluntary character of your beliefs - "I can, therefore I must" is not a convincing line of argument for most, and those who find it convincing typically do so because of deeper, personal reasons.

I think you make a good point when you say that a socially healthy, tribalistic society will not need supernatural explanations for anything in order to function. With that said, it is important to be clear about what we mean by "function" and "supernatural" in such context. Resorting to theistic, creationistic and other such explanations is probably indeed not necessary and maybe not even desirable, but it should be noted that even higher principles such as self-possession, self-control, honour, and virtue are all "supernatural" principles - they can not be explained by or reduced to nature. Nature is concerned with the blind survival of the individual organism in any way, and at any cost. It does not exclude shameful or pathetic forms of existence. What makes these intolerable to us is precisely the "supernatural" or spiritual element, and the more prominent this element is, the more intolerable we find them. This element is not the same thing as materialistic rationality, because rationality can be used to justify anything, including the acceptance of the most intolerable forms of existence. Consequently, the element that interests us is something else - the spiritual element. Without this element, a tribalistic society could certainly survive, but it would not be a pretty sight at all, and would probably not look too different from what we have now.

If what I have been saying so far sounds agreeable to you, then I think that you will also agree with me when I say that the real issue today seems to consist not in embracing materialism, but in arriving at a true, correct and complete definition of spirituality, and then articulating a practical form of it that is suitable for the current circumstances.