[vasilipupkin]

states do have very different welfare policies. Some more generous than others. Texas has comparatively little relative to Massachusetts. Guess which way the net flow of people that are supposed to benefit from those policies happens

[MagicWishMonkey]

Poor people don't have the resources to move around the country.

Wealthy people are the ones who relocate and they don't benefit much from social welfare programs (if you ignore tangential benefits like not getting your car broken into by someone who needs money to eat).