There are examples of this sort of cooperation to survive in primitive human societies. Inuit Eskimos will share their game with the whole village. No one is allowed to starve, even if they don't participate in hunts (they are despised and looked down upon though).

I would assume the same practice were true for most hunter-gatherer societies. But one aspect that led to this "wealth" sharing is the fact that in primitive societies people living in the same community were closely genetically related.

Matt Ridley touches tangentially on this topic in his book "The Origins of Virtue".