Continuity mistake: Dick's plot in this episode is that he learns about the concept of tipping. However, the season 3 episode "Eleven Angry Men and One Dick" showed that Dick was already familiar with the concept of tipping when he tipped a bailiff during a jury selection process.
3rd Rock from the Sun (1996)
1 mistake in Sex and the Sally
Dick, Who's Coming to Dinner - S5-E6
Dick: Does anyone remember why we all decided to be white?
Harry: Oh, um, I went with white ‘cause I thought it'd be a little cooler in the summer.
Tommy: Well don't you remember, Dick? All the television signals that we picked up in outer space were filled with white people.
Sally: Oh, except for that, uh, that black nerd with the hiked-up pants and the oversized glasses. What was his name?
Tommy: Bryant Gumbel.
Sally: Right.
Tricky Dick - S3-E3
Trivia: Dick's rant about his perceived evils of rock music is identical to Reverend Moore's (also played by John Lithgow) opposition to dancing from the film "Footloose."
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