Crowning Moment of Heartwarming: Meta example. According to the commentary, despite Bud and Lou's notorious tempers off screen, they never subjected the three monsters to any of their tantrums, since they respected them so much. They clowned around with them, but never fought with them.
"Funny Aneurysm" Moment: In a scene set immediatly after Talbot first shows up, Chuck and Wilbur walk into his room the morning after he wolfs out and find it completely wrecked. Chuck comments, "Man, what a bender he was on!" In Real Life Lon Chaney had a drinking problem and, according to the film commentary, spent his weekends getting drunk and getting into room-smashing brawls with a friend.
Hilarious in Hindsight: Vincent Price's cameo in the end is even funnier now than it was back then. While Price had starred in The Invisible Man Returns several years earlier, it was a one-off and Price was not known at the time as a horror film star. It would be another five years after this movie before he was cast in another horror film (House of Wax), and it would be another five years after that before he began to regularly star in them. Today, Price's cameo feels like the passing of the torch from one generation of horror film stars to the next.
I Am Not Shazam: Aside from the title, Wilbur calls The Monster "Frankie" when he tries to reason with it.
Otherwise averted, as characters who should know better (such as Dracula) refer to the Monster as "Creature" or such.