Odd Gambling Buddy

So I have a a buddy who loves blackjack but will not hit anything over a 12. Nothing, doesn’t matter what the dealer is showing . I’m used to it but it throws everyone off. I get that this is not basic strategy but it’s his strategy. I warn people who join the table “hey he won’t hit anything over a 12.” Then after a few hands they get pissed. Not really sure what else I can tell people joining the table. He is going to play how he plays and I’m OK with it, it’s his $$$. Not sure why others can’t get on board with it esp after I give the disclaimer each time. Anyone have advice on how to handle other players? Anyone have similar friends?