The reason for this is that if one state has better social programs then another and higher taxes the poorest are going to move there, and the high earners are going to move away.
The idea that the poor will mass migrate to California and the rich will mass migrate to South Dakota is pretty unrealistic. The poor can't afford to live in California even with social assistance, and the rich don't want to live in South Dakota no matter how low the taxes are.
Because money buys stuff taxpayers want. Middle class people want good schools and functioning transit and to know they're going to have a secure retirement. The premise of having the government do these things is that they can do them at least as well as the market. If they succeed they'll have no trouble attracting people to come there and pay taxes in exchange for receiving those services. If they fail and are then out-competed by other states that do better, whether by leaving things to the market or otherwise, isn't that a good thing? It requires the underperforming states to improve or lose population.
I might be off the mark here, but from my understanding wasn't unrestricted migration one of the big drivers behind Brexit? Or at least the idea that the "poor countries" were "taking advantage" of the "rich countries"?
It’s true for blue collar workers as well: try hiring a contractor to remodel your house and then watch them leave the job unfinished because they got a better paying gig in UK (that actually happened to a friend of mine)
The thing about rich people moving to places with lower taxes and poor people moving to places with more services is that it's the sort of thing that seems intuitively obvious until you actually think about it, and you realize it's like arguing that lakes are impossible because water evaporates.
It's not that water doesn't evaporate. It's not that poor people don't prefer more services and rich people don't prefer lower taxes. It's that everything is not one dimensional and there are other factors that outweigh that one by enough that the lake is still full of water.
Leaving the EU will mean more migrants from outside of the EU - so will actually cause the situation a lot of Leavers were worrying about to get a lot worse.
See Robert Peston's WTF? for details.
Are you serious?
Expand your timeline.
Those high earners will screw up the economy of their destination state accidentally gutting the lower middle class, institute social programs to deal with the all the problems this creates, realized they just created the same dystopia they fled and move again.
It's like a perverse form of rolling upgrades.
You can see this process in action in places like CO and the PNW states which are starting to flip from "rich people move here" to "poor people move here". TX will probably start flipping soon.
Major urban areas with lots of job opportunity seem vacuum up the wealthy regardless of the state wide trend (no matter how bad NY state gets upper middle class people in search of a lucrative career will be moving to NYC). I'm not sure how that plays into things.