It also makes sense for richer people if the living conditions are better because people poorer than you have a safety net so you aren't impacted by their social problems, or if, e.g., universal government benefits like healthcare end up being better value than what is privately available elsewhere, perhaps because of economies of scale, or because you are effectively a co-owner of a monopsony purchaser, or because the safety net for the poorer people supplying the service means total labor costs can be less without them living in unacceptable security.