During the fight scene, one of the surfer dudes manages to knock a muscle guy through a wall in front of a yellow surfboard and red-topped table. When Candy starts dancing, the second guy she "bumps" goes through that same, now undamaged, wall in front of the same yellow surfboard and red-topped table.
A helicopter is hovering over the beach. It is shown equipped with pontoons but its shadow clearly and repeatedly shows a helicopter with metal rails for landing gear.
In the opening scene when Frankie and Dee Dee are driving to the beach in their hot rod it shows Frankie singing with no windshield wiper on the car in the close-ups, but in the wide angle shots it clearly shows the windshield wiper sitting at the top of the windshield.
During the first surfing scene, Frankie and DeeDee both fall off the surfboard they're sharing. When they get out of the water, both of them have fully styled hair. So do all of the guys who had been surfing.
During the first surfing scene, the waves they're surfing are bigger than the waves when seen from the beach. The waves are nearly non-existent when seen from the beach.
Frankie refers to the "people for people" line directly after the scene in which it is said. However, he had already left that scene entirely by the time it was said and couldn't have heard it.