Yeah, he's doing it wrong. Sorry to hear that.

So he gets free food at the restaurant and doesn't bring you a doggie bag? Now I'm going to have to land where Mike did:

Why are you still with him?

Take his pot and tell him you smoked it, then spout whatever excuse he gave to you for taking the money back at him. If he gets jostled enough, point out the irony in getting clean of hard drugs and treating pot like it is one.