Good points and centralized infrastructure does seem key , but I think the biggest factor is the cost of housing. If Houston is half the cost of LA you’re going to have a lot less homeless to begin with and it’ll be a lot more affordable to over then housing.

This overlooks the weather factor. if you’re homeless and have the chance to get a bus to LA, would you rather try to survive in the streets of LA or Dallas (or Houston)? Easy decision.