He thinks that stealing and borrowing are the same thing.

If your roommates don’t do something that annoys you a little bit, you’re probably living with a robot and not a real person. If you decide to cohabitate with other people, you have to get used to the fact that they’re going to do little things that you don’t like, and you’re going to do little things that they don’t like. It would be borderline impossible to find a living situation where everyone is never annoyed with each other, and if you keep trying, you’re never going to stay in one place for very long.

The most important thing is figuring out which annoyances you can accept and which you need to discuss with your roommate. If the bathroom floor is soaking wet every time they take a shower and they don’t bother to clean it up, it’s worth having a conversation about. But if they forget to take the trash out once after consistently doing so before, it’s probably best for the household if you let it go. 

There’s a big difference between failing to do the dishes and causing criminal-level harm to your roommates. A lot of us can probably deal with a roommate who is slightly messy and occasionally leaves the lights on before going to bed, but you shouldn’t have to accept a roommate who is taking your stuff without permission. The roommate in this story did something far worse than eating his roommate’s groceries. He literally stole his tuition money from him!