From my last post on this topic: I think critics of Wal-Mart assume everyone has a good job till Wal-Mart moves to town. Not true.
Much of the free-market stuff that I read assumes everyone is smart, everyone is mobil and everyone is ambitious. If they aren't all three, that's just too bad. Because the author is all three, and he doesn't feel any pity for them. But living in small towns in depressed areas has convinced me that not everyone has all these options open to them.