I don't interpret that as hypocritical. Whether legality equates to morality doesn't matter. If you get caught, there can be serious consequences (legal penalties, kicked out of schools, etc.. all depending of course on the circumstances of the party, the party-goers, the school, the state, etc.). These risks didn't exist when she drink in college. They do now, and it's not unreasonable for a parent to want to prevent these things from happening to their child. Their opinion can be 0% percent judgement based (in the sense of "passing judgement".