Was I being pettty? Guy goes south

Playing 1/3 I have about a $500 stack off a max BI on $400. New player sits and he's a total fish. Calling everything to the river but starts off running hot. Takes about $100 from me after hitting a 3 outer then gets into a big pot with another player where he wins about $300 after hitting running flush cards. I noticed in that pot he got 2 black chips from the other player. He then gets up and goes to the bar. But his chip stack doesn't look right. All the black and green chips he had are gone. His stack looks to be around $500. I mentioned something doesn't look right and the the player next to him says he put a bunch of chips in his pocket. Then that player who saw it racks up and leaves. The dealer says she didn't see anything and doesn't seem like she wants to say anything to him. I insist that something needs to be said when he returns. When he gets back the dealer asks him if he pocketed chips and he admits he did. Claiming he took off $250. Dealer tells him he must keep the money on the table and hes not happy about it. Says that he will just leave and go to another table. Eventually he puts the chips back on the table and continues to play. Over the next few hours he's broke. Was I petty in insisting since what he left on the table still had us all covered? Other players at the table didn't really seem like they wanted to say anything about it. I wasn't rude in any way. Just telling him rules are rules.