These are what we call the 'YMMV items.' Things that some people find in this work. We call them 'your mileage might vary' because not everyone sees these things in the same way. This starts discussions in the trope lists, a thing we don't want. Please use the discussion page if you'd like to discuss any of these items.
Dude, Not Funny!: Dragging a dog to death just isn't funny. The cop who pulled Clark over for it was especially unamused.
It was a horrible dog, at least.
Well it more the circumstances of it that was funny. Clark was kinda distracted while packing up everything. And you gotta admit the scene with the cop was hilarious.
At least they only showed the dog's collar. In the short story that the movie was based there is a very graphic description of Dinkie's remains, and he wasn't even a mean dog! Also there's a part where Clark purposely kills another dog with a revolver.
Averted at one part. It was originally planned for Aunt Edna to still be alive when she was on top of the Griswolds' car. It was later changed when it was considered too mean-spirited.
Who's to say she wasn't alive by the time Normy came back?
Ear Worm: Lindsey Buckingham's "Holiday Road", which serves as the movie's theme song.
Also the "Pig In A Poke" theme song from European Vacation.
Harsher in Hindsight: The "they don;t close Florida" line might qualify in light of the recent immigration incidents.
Incest Yay Shipping: Dana Barron and Anthony Michael Hall as Audrey and Russ seem closer than a normal set of siblings would be, which led to speculation they had a offscreen relationship.
Nausea Fuel: The family at one point stop off at a picnic area to have some lunch. As they're eating the sandwiches they notice they're soggy, And then it hit them that Aunt Edna's dog urinated on the food. The family is understandably disgusted but Edna just shrugs and continues eating. Ugh.
Retroactive Recognition: A pre-Seinfeld Julia Louis Dreyfuss has a small role in Christmas Vacation, as one of Clark's snooty neighbors. Doris Roberts also has a supporting role as Clark's mother-in-law.
Sequelitis: With a different director, no creative input from Harold Ramis or Chevy Chase, completely different characterization for Russ & Audrey, and some of the better gags being telegraphed too far in advance, European Vacation is nowhere near as beloved as its predecessor or its follow-up Christmas Vacation.
What an Idiot: The whole mess of a vacation would have been avoided had Clark (or even the far more rational Ellen) made a simple phone call to Wally World to confirm it was open for the season; they would have learned it was "closed for repairs." (Then again, phone call equals no movie and no fun for us, the viewer.)