True, but only about 2-3000 individuals out of the hundreds of thousands of millionares in China went down this path. Even if you say they chose other western countries you maybe have 1-5% of the wealthy doing this. Hardly a majority.
And the US has one of the lowest thresholds for investment to get this investment visa - 500K and 10 jobs. Buying a McDonald's franchise would easilly cover that. So the actual % is probably around 1%.


I think this has more to do with the kids education, and having an easy out in case they ever decide things really do get bad enough. Polution is just an easy excuse since as others have pointed out, most still continue to reside in China since that's where their gunxi gives them business.