Don't hate the player, hate the game. If they're not going to say anything to him, what's his incentive to stop?
I think it seemed longer in this match because it was just so damn boring. I timed him a few times myself, and it wasn't actually that long most of the time. I find it hard to believe that was the average.
He usually does it in tense situations and close matches, so I was surprised how long he was taking between points in the third set when the match was over. He really slows down when his serve games go to deuce. If there are a couple of deuces, it's always quite a long game.