Hotel Riddle

Three guys went to a hotel manager for a room. The manager said a room would be $30. They all paid $10. The bellman took their luggage up to their room, but when he came back down the manager told him that he charged $5 extra for the room and to bring the $5 back. The bellman was mad though because the guys didn't tip him so he took $2 and gave the men $3 back. So each man ended up paying $9 for the room. 3 people x $9 = $27 but $27+$2 = $29
Where did the extra dollar go?
Answer