I think the point is that historical societies are full of unbalanced social relationships, or "freeloader problems". Slaves and serfs worked for their masters.

I think the point is that historical societies are full of unbalanced social relationships, or "freeloader problems". Slaves and serfs worked for their masters. Parents provide for infant children, and adult children for elderly parents. Kings and lords receive tribute and service to the extent that they are due, and sometimes demand more. Priests take in offerings and perform rituals - often any barter here is directly with the god ("Poseidon, bring our ship safely to harbour and I will sacrifice an ox for you") rather than the priest.