Speaking as a former college history teacher, all cultures tend to be subcultures to a certain extent as they exist in a greater balance. Generally, though, warrior cultures are almost always at the top of a society or top adjacent for what I assume is obvious reasons and often do create their own culture within a culture at worst. Hereditary military classes are so common, though, that they are something you can never say isn't a natural part of human society. They depend, obviously, on other castes to survive but an interesting fact is the Klingons constantly and pardon my Kling but "pissing and moaning" about how things were always better in the old days when men were men and peasants were peasants also reflects how many of these cultures eventually developed.
I always wanted the honor-obsessed culture of TNG to be a natural outgrowth of peace as like the samurai, you don't actually think about honor and status all that much when you're murdering each other. You only have time to do that when you're not in the chaos of war.
So I don't disagree with you so much as think you're looking at the glass as half-empty versus full.