Generally the older students tend to party in moderation and focus on studying for their major. Most students who have been in college a while have just partied themselves out. People choose to further their education for many reasons. Many younger college students go because of pressure from family and parents. Generally older college students further their education for a better career.
Many people love the enjoyment of going to college just to learn.
Then there is that group of college students who just attend college to party. As you can see there are many different reasons for furthering a person's education.