I'm not talking about 'picking and choosing the most expensive parts of the country to live in'. I suspect poorer people may rely more on geographical proximity on getting social support from friends and family than do richer people, who can afford to travel regularly and who anyway tend to have more cultural capital to fall back on. So making poorer people move away from their roots, particularly if they have young children , can be more painful.
In any case I do not think ghettoization on the basis of wealth makes for a very happy community.