The first reason to be involved in college is to allow you to give back to the community. This could be in multiple ways such as volunteering for the local hospital or being an officer in a club or academic society.
Secondly, being involved in college helps you become a part of the community around the college. Getting involved with the community helps you network with people that have the same ideas or same interests as you. Making connections with people that have the same interests as you can help you when you need help in school or when you need a job. In addition, when you need help studying for a test or when you need help writing a paper in a certain area, having friends with this knowledge should help you.
Being involved in college also helps you discover your passions about certain things or ideas. It also helps you learn your strengths and weakness in multiple areas of life. Maybe you are good at art but terrible at math. However, you would not know this until you actually took the time to try different things. College is about trying new things and about having experiences of a lifetime.
Being involved in college can also increase your GPA because you are actually interested in the classes that you are taking.
Being involved in different organizations in college also helps you build a resume. This helps you become ready for the real world once you graduate from college where you can obtain a job. Most of the time students involved in extracurricular activities also do better in school and receive better grades.
Being involved also helps you grow as a person. Being able to experience things that you never thought you would experience is always a good thing. Many people learn more about themselves in college than they ever thought was possible.