What does it matter whether we think his actions are "perfectly normal" or unacceptable? The point is YOU don't like him doing it so you have to talk to him about how it makes you feel when he does such things. You have to ask him to stop doing them and if he won't, well then you have decision to make as to whether you can stay with him and be able to be non-anxiety ridden when he does or you leave him if you can't be accepting and calm and trusting that he won't be sampling others "goods."
Your call and what we think is totally irrelevant. Unless of course the vote will make him do what you want.. then in that case I vote he stop being so shady and only hang out with his "friends" when you can to. If he posted first then I'd vote on what he wanted because it's a useless as tits on a bull knowing what we think about it when it's you that doesn't like it.
“The willingness to accept responsibility for one’s own life is the source from which self-respect springs.” ~Joan Didion