Trivia: In the beginning of the movie, when the candy store owner is singing the candy man song, there's a spot towards the end of the song where he lifts up his counter to let all the kids in. Watch the little blonde girl as she gets walloped in the chin by the counter. (00:04:30)
Trivia: Of all the child actors who played main characters in this film, Julie Dawn Cole is the only one who continued to act into adulthood.
Trivia: Peter Ostrum won the role for Charlie while acting at the Cleveland Playhouse children's theater in 6th grade. He had no acting experience after that, and is now a veterinarian.
Trivia: While on the Wonkatania, the Oompa-Loompa thought he was really steering. The truth is the boat was actually moving on a hidden track. Director Mel Stuart didn't tell the actor this because he didn't want to ruin the illusion.
Trivia: The novel's writer, Roald Dahl, hated this movie version of his story.
Trivia: When Wonka yells at Charlie, Charlie wasn't told beforehand that Wonka was going to be yelling in the sequence because director Mel Stuart wanted to see his real reaction. Gene Wilder wanted to warn the boy, but Mel Stuart forbade it.
Trivia: Only the ears on the jelly bears that Violet was eating, was edible.
Trivia: When Augustus gets caught in the tube, Wonka says "The suspense is terrible, I hope it will last." This is a quotation by Irish writer Oscar Wilde.
Trivia: When the newsreader announces the finder of the fraudulent fifth ticket, the picture he holds up is actually one of Hitler's last known henchmen, Martin Bormann.
Trivia: Augustus' father is stated to be the town's most prominent "parve butcher." "Parve" means "lacking meat and milk", therefore there is no such thing as a "parve butcher."
Trivia: Oompa Loompas were originally written, by Dahl, as caricatures of African Pygmees. the producers felt that this was offensive, this is why they are orange.
Trivia: Gene Wilder (Willy Wonka) would not do the film unless it included the scene in which he walks out of the factory lame and then falls and does a somersault. Wilder said that he wanted to make sure no one ever knew if the character was lying or telling the truth.
Trivia: Michael Bollner, who played Augustus Gloop, lived in Munich, where the filming took place. He used to change at his home in the morning, then turn up for filming. He also couldn't speak English and had to be coached on his lines, which made it hard for him to bond with the other kids in the cast.
Trivia: The girl in the classroom who says she opened "about a hundred" Wonka Bars, is director Mel Stuart's daughter.
Trivia: Julie Dawn Cole, who plays Veruca, doesn't even like chocolate.
Trivia: Although ostensibly created as a kid's movie, Willy Wonka has maintained its popularity as a stoner classic.
Trivia: The Wonka factory was inspired by the notoriously secretive Mars Corporation, nicknamed the "Kremlin of candy".
Trivia: In the scene when Wonka shows the kids the 'Lickable Wallpaper,' he says, "And the Snozzberries taste like Snozzberries!" This is odd, because in another Roald Dahl book, he refers to 'Snozzberries' as male genitals.
Answer: Closed circuit security was invented in 1942 and came into common use in the late 60s and early 70s. Beyond that, Wonka could have had Oompa Loompas monitoring the group or simply noticed that they were gone and guessed.
Greg Dwyer