The difference is that people didn't choose to get polio. But they chose to go to college knowing that they would get into debt and then dug their way out of the consequences. If the next generation of college-goers would not have to put up with the same crap, that would mean that their own self-inflicted suffering was meaningless. At that point, cognitive dissonance kicks in and people make the illogical argument that "if I had to suffer, they should have to suffer too".