Perhaps you look a bit more menacing? So far no problems but just another example that if human judgement is involved all bets are off.
I don't know why but the last two trips I've quailfied for the prescreened, no shoes off, etc line. Very nice.
I'm in the Pre-Check program now, so as far as TSA is concerned, I don't have to take off the belt anymore. But in other countries, their security screeners sometimes still make me take the plastic belt off.