Even if you don't need to because you can afford college, it is fun to have a campus job. Not only do you gain valuable work experience but you also understand how it feels to be independent while having a job. I do not need to take a job because my parents pay my whole tuition but that doesn't mean I can't help them and myself out.
It is hard for students who can't afford college and the facilities I do not need to think twice about because I am privileged and every day, I'm thankful for that. I recently applied for a campus job in the restaurants UCLA provides to the students and I got it. I haven't started yet but I am really excited to.
A friend of mine asked why I am taking a job if I don't necessarily need the money. Even if I don't need the money, every penny counts to help my parents. Also, equally importantly, I will be able to spend the money I earned without having the guilt of spending my parents' that constantly following me around. I will buy the things that make me happy with the money I earned from my hard work and that will make all the difference.
Having a job in college also makes you understand the expectations of the workplace that you are going to join fulltime after you graduate. Getting a job before that allows you to understand how to understand and navigate workplace culture. Graduating and plunging into the workplace without having an idea of it is going to be overwhelming.
Having a job as a college student allows you to make mistakes and mend them, something you will not be able to do when you get out of college. Right now, as a college student, you have a leeway you will never have in another time period of your life. You are able to make mistakes and learn from them, and there won't be drastic consequences to your mistakes.
Also, getting a job in your college is not hard because you don't necessarily need to have prior work experience, just a friendly demeanor and a willingness to work hard.
Getting a job also looks really good on your resume as employers understand that you are able to handle the college course load and a job simultaneously. It shows how responsible you can be and how well you can manage your time.
Basically, as Sylvia Mathews Burwell says "Job training empowers people to realize their dreams and improve their lives."