Grandpa Joe: Mr. Wonka, I don't know if you remember me, but I used to work here in the factory.
Willy Wonka: Were you one of those despicable spies who everyday tried to steal my life's work and sell it to those parasitic copycat candy making cads?
Grandpa Joe: No, sir.
Willy Wonka: Then wonderful, welcome back.
In the scene in the glass elevator, when Mike Teavee wants to push a button, he presses the TV Room button. The elevator stops going down and immediately moves horizontally. The characters within the elevator are thrown against the wall from the sudden change. However, they are thrown against the wall that is in the direction the elevator is now moving, instead of the opposite wall as they should have been.
The many Oompa Loompas in Charlie and the Chocolate Factory are all played by the same man - Deep Roy. They used CGI to duplicate him. He would do a ton of different dance moves so when it's all put together, it would look like there were a bunch of different Oompa Loompas.