Rugby fans who thought they were parked legally near the Albany park-and-ride were towed and forced to pay $230 to get their vehicles back after Friday night's Rugby World Cup opening.
Confused car owners said they did not see any signs in the grass field near the Albany transport station saying it was not legal to park there.
Allan Montefiore left his car at the Albany Park and Ride at 3pm.
"There was a driveway into the grass and there were cars everywhere so we just assumed that for the Rugby World Cup the park-and-ride opened up the grass section."
Mr Montefiore said that when he arrived, "40 to 50 cars" were already parked on the grass area. He returned to the park-and-ride at 10 the next morning to find his car gone.