Why do players do this? Slow roll in the Trop 4/8 game in AC....

[nineinchal]

Villain on the button. Hero on the big blind.

Hero re-raises villain pre-flop. Flop comes J-9-rag. Hero bets, villain calls. Turn is a 5, Hero bets, villain raises, hero calls. River is another 5. Hero bets, villain raises and says " I know your don't have a five". Villain then says "What do you got?" The hero says "you raised, what do you got?" Villain opens up a pair of fives for quads. Hero says "Cute, you know I don't have a five, I got aces, that's what I got." I thought there might have been more fireworks after that, but the hero took that in stride, considering the beat that was put on him and the way the villain was a real douche.

What's wrong with people? This is only a lousy 4/8 game.