A long long time ago when most people's parents didn't suck, parents themselves would talk shit about this guy's parents for wanting to make him pay.
He's their son. He seems like a good kid seeing how he's a college boy and judging by the fact that his parents are even willing to have him in their house.
He's not some kid off the street, a typical tenant, or a friend of the family - he is the family. If you ask me it's pretty stupid charging him rent.
You do not teach a boy responsibility by putting him in this kind of situation. I'm sure that he KNOWS that he would have to pay more rent elsewhere and that he will have to pay many things in his life, but does that mean he HAS to now? How about in 20, 30, or 50 years when his parents no longer walk the Earth? Are they going to donate all of their worldly goods and fortune to charity because they want to teach their son "responsibility?" Please.
I live at home and don't pay rent. I could - but I don't. Instead I spend the money I would normally be spending on rent on investments, educational materials, and decent fun. Someone here would claim that this does not teach me responsibility, which is clearly false since my finances are in better shape that quite possibly any part-time worker my age.
It teaches me something more important than responsibility - how not to be a dick and charge my own son rent when I'm 40 years old.
-Warik