Why do colleges care so much about extra curricular activities when college hours aren't even that bad?

A friend of mine in high school was so anal about her extra curricular activities to the point where she would not come home from school until around 9pm!!! I, however, didn't do a single activity and still managed to get accepted into the dental hygiene program at my college due to my grades. So my question is why do certain colleges act like you need extra curricular activities when in college you can go to school 2-3 days a week and still be a full time student? Are colleges hoping you'll do extra time there as well to give them more money?
--------------------
Extra curricular activities show a college you take part in school outside of the classroom, and are a well-rounded person. And secondly, they hope that you will continue your interests in their clubs and organizations. Not necessarily for money, but to just keep the social domain of their school running and get kids attracted to their school. For many of the upper schools in the US, you won't get in without some form of extra curricular activities.
Source