It's not just weapons, either. It's - abilities, magic, whatever you want to call it, too.

[Not so much for Nick himself, though he has noticed it a bit, but more in people like Monroe and Julian.]

Just that he stepped on Deior's toes, and was in trouble for 'aiding a fugitive.' The way I see it, he's either learned his lesson and isn't going to be eager to help anyone any time soon, or - well. He's done it once already. Not sure which it is yet, though.