That guy sounds like a difficult individual. If you weren't his roommate and he came out, I feel like his perspective could change, but he is deeply rooted in bad habits. Cleaning after yourself is a bare minimum.
I just went on holiday with some guys I used to go to school with for two weeks, and it was a real eye-opener on some of their habits. They didn't clean their dishes and cutlery after using them - just let them stack in the sink. They were about to leave 24 eggs uncooked in the fridge because they were "caged eggs", so they tasted funny or made one of the guys' stomach feel weird. I dunno, I ate through them all, and I didn't feel anything was off.
And because three of them were practically smoking a pack a day, they filled a large, empty popcorn bucket with the ashes and butts.