Revealing mistake: The last scenes of the grand finale/climax occur in an abandoned amusement park that's supposed to be in inland Indiana. But several shots with the Pacific Ocean "lurking" in the background (despite the cameraman's best efforts to hide or avoid it), as well as palm trees, and ocean sounds intruding on the soundtrack, reveal that the actual shooting location was in Southern California.
Revealing mistake: Marcia demonstrates an early home video recorder at the trade show. Her camera set-up should record her test subjects from a lefthand angle. But her tapes show them all from a righthand angle - the position of the actual studio camera.