Deliberate mistake: In the final scene when the four cars are driving away there is a road sign that shows how many miles it is to Chicago (where the main characters are from). In reality there would not be such a sign because there is not one direct route from Vegas to Chicago. A typical road sign would show the nearest cities.
Vegas Vacation (1997)
1 deliberate mistake - chronological order
Directed by: Stephen Kessler
Starring: Chevy Chase, Randy Quaid, Ethan Embry, Beverly D'Angelo
Genres: Comedy
Continuity mistake: Towards the end of the movie when Clark Crashes into Wayne Newton's house you can see the hood of the tour van is not damaged. A few scenes later when they pull up to the casino the hood has a lot more damage to it. (01:15:22)
Marty: You don't know when to quit, do ya Griswold? Here's an idea: Why don't you give me half the money you were gonna bet? Then, we'll go out back, I'll kick you in the nuts, and we'll call it a day.
More trivia for Vegas Vacation
Question: How much money did the family win after playing Keno?
Chosen answer: $25,000. Given to the Griswalds by Sid Caesar's character just before he passed away.
Answer: The sign said $30,000.