Justin Bieber definitely makes a bunch in the bank, but he doesn’t seem to know so much about banking. When the teenybopper star and his crew hit Susan Sarandon’s ping-pong club SPiN Wednesday, they were directed to a private room away from the masses, but told they’d have to give up the space at 6:30 p.m. for a private party. When the time came, a spy says, a SPiN staffer popped into Bieber’s VIP room to tell him it was time to go. The singer’s posse didn’t want to leave and started to kick up a fuss, but they were told, “We’re really sorry, the room is booked . . . J.P. Morgan is having a private party.” Our spy says Bieber then piped up and shot back, “Why does he get the room and not us?”