American universities aren't just about education. Or even research, for that matter. They're often about providing a "life experience" for undergraduates. So you have a huge investment in sports, entertainment, and living facilities that are basically unheard of in other countries. Plus, all sort of administrators and advisors who help students in a variety of different ways. These add up to a great experience, and…
Some people treat college like a four year vacation with planned activities. In which case the price is really quite cheap. Looking back, I was guilty of this attitude at various times.
In general, many people need to detox from a childhood that lacked sufficient freedom to explore and become a full human being. Their internal programming then takes college and its new freedom as an opportunity to rectify that. It is quite a reasonable approach given our K-12 schooling setup and its intense control of children's time during the day.