Yes, it’s The Great Escape, the movie that teaches saying: “Thank You” is a bad thing.
When I was a kid, every time The Great Escape came on TV, it was a big deal. But in once scene, escapees try to board a bus, and after showing their passports and making niceties with the Gestapo, one of the Gestapo says: “Good luck,” and one of the escapees gets tricked into saying: “Thank you,” (in English) and that’s how they get caught.
Well, after a long chase the escapees both get caught and are then shot as spies (Oh, um, spoiler alert?). And so if you have kids and they do not want to say: “Thank you,” you know who to blame: the movie: The Great Escape.
They obviously only made this movie to make kids never want to say: “Thank you,” ever again, and for kids always to have an excuse not to have to say it. (“Hey, it got Richard Attenborough killed. He directed Gandhi! How am I ever supposed to live to make Gandhi 2 if I have to say: ‘Thank you’?”) Why else would they have made it? (I am on to them!)
This is the scene I am referring to from The Great Escape:
(BTW: I am obviously only joking, although you can read it this way if you choose. And of course I know that Richard Attenborough was not the one who was tricked into saying: “Thank You,” but he was killed all the same. So if you ever say it, obviously he will be killed, and it will be your fault.)