We did not evolve to live in societies where 1% of the population controls 50% of the resources. Inequality, in and of itself, causes all kinds of dissonance and unhappiness for humans. And to make matters worse, we now tolerate a level of poverty that would actually have been unheard of for most of human history. Back when we lived off the land, when nature provided us with what we needed to live, and when we took care of each other, we actually worked far less in order to meet our most basic needs than the average employed working class American does today.