When we look back on past civilizations we do it with a relatively slim understanding on what, why, or how they did things besides the basic drives and needs of life. The further back in time, the more we have to "guess" what we're looking at. So usually we just assume that so far back in time the civilizations must have been simple enough that their main focuses (besides... living) were religion or war. It's sort of a running joke among archaeologists that when something is unexplained you immediately attribute it to religion/ritual. [0] Sometimes it's hard to imagine that once in a while, people many millennia ago might have behaved just like modern humans since we haven't changed
that much in the meantime (biology/evolution). [1] [2]
[0] https://www.quora.com/Do-archaeologists-have-a-tendency-to-s...
[1] https://satwcomic.com/humans-never-change
[2] https://me.me/i/lesbianshepard-if-an-archaeologist-says-an-a...