But this is exactly where our environment differs profoundly from the ancestral one: most of us live in a society closed over resource production. We still need food and other means to survive, but now there are no freely accessible sources of them - we're all gating access to resources for each other. Which means I always have to do someone's bidding if I want to live. I have some choice of whose bidding I'll do, but this means that I'll eventually reach a point where changing the person whose bidding I do is less effective than just doing more for the current one.