We're talking about smart people and inevitably they're going to look at friends who've opted for the corporate world and do the math. Certainly as long as the promise of a big payoff is there, then the math might weigh in favor of doing a startup. But it also might not. That whole time value of money thing says that sacrificing income in your twenties is going to hurt you a lot more in the long run than sacrificing income later on.

edit: Of course, right now the "whole time value of money" is basically negative. ;-)