When Cousin It arrives, he was assumed to be driving and came into the house alone, but he exited the car from the rear passenger side.
In prior depictions, Lurch was often seen with a feather duster. The concept of "dusting the house" by using a vacuum cleaner running backwards to add dust was a running joke from The Munsters.
Throughout the film, various characters refer to the Addams family members in the plural as "Addams." The correct plural is "Addamses."