Humans have a lot of options for how they'll live their lives.
Culture is a group which all make the same decisions. So, as a stupid example, one can choose to admit lots of foreigners or none at all. The first culture will develop means of dealing with contrasting belief systems in an orderly fashion, and will shy away from institutions that require homogenous beliefs. The second culture will have lots of institutions that require homogeneity, but will have simple, crude methods for dealing with heterogeneity.
Hunter tribes don't need psychologists because their lifestyle doesn't put great strain on the human mind. City tribes need a plethora of support systems for the mind, because humans are maladapted for the city environment.
For less stupid examples, there's more than one way to organize a city. Different cultures can choose different, incompatible ways, and still end up with a thriving city as long as their decisions are relatively consistent.
Culture is a conflated thing. Cultures develop, or previously had, a particular character. One can see the character puts a bias on how these decisions are made. It also affects the character of the culture's art. Similarly, the art's themes will be applicable to the relevancies of the culture - decisions to still be made, or difficulties the culture has in living up to its own decisions. But, strictly speaking, the set of life decisions is a different thing than the arts a social group creates.