Have you considered that perhaps you have causality mixed up here? Perhaps it's not that only the wealthier ~39% of people want to go to college, but rather that the bottom 61% don't want that economic burden.
I certainly agree that more people would be going to college if it were free. 80% of people? I'm skeptical, but the existing people sending their kids to college (who can afford foregoing that income) would certainly appreciate the giveaway
Those who can afford it as easily as you say are the kind that will go to private schools in a heartbeat
Those who are struggling to afford it are the ones who will appreciate the help