I don't see why you are in such a tizzy about this rent thing. He's a full time college student. It's not like he's working 40 hours a week and still expecting his parents to pay for his rent. If he was living on campus in a dorm would you be all bent out of shape because his parents were paying his dorm fee?
My 20 year old son is in college and we pay for his dorm housing and dining hall meals. My daughter is 21, is not attending college, has a job, does not live at home, and pays her own bills.
So, am I a bad mother because I pay for my son's living expenses when he only has a part-time, minimum wage job, as well as a full course load at a university?