Because at that time, the universities and the government, were gladly lending that kind of money to students - with zero education about how it would impact their long-term futures. Things tightened up a bit later, but the money was flowing freely and if you were a student from a lower income home, who’s parents couldn’t help, you needed that much money to barely have a $30k per year lifestyle (close to poverty level). At the time, in order to graduate in 4 years, most colleges demanded that you take 5-6 classes each semester, which was more than a full time job. Everyone I knew, including myself also worked at least one, if not more than one part-time job to supplement.