I think, and would hope, that medical school interviews would help to weed out those who are just in it for the money. Even in highly-paid specialties, you have to want to do the work you do.

Were there people in my class who were in it largely for the prestige, etc.? Sure. Those people tended to go into high-profile specialties like plastics. But they were the minority, and I think that schools recognize in general these types of students are bad for the profession.