Other mistake: In the movie, as the jeep comes up to Byron Buckles' plane, the jeep rolls through previous tracks from previous takes.
Other mistake: When the General arrives at Camp 13 and is greeted by Klink, he notices Hogan and ask Klink who he is. Klink only says he's the Senior POW, the General sends his Aide to get Hogan. The Aide addresses Hogan by name, but Klink never said Hogan's name. (00:07:40)
Other mistake: Usually, the picture at the podium has the microphone "bug" for Hogan, and it's blatantly obvious, except to the Germans. This time, there is no bug, but an extra picture that the boys can take the eyes out of and listen in.
Answer: It's a comedy, not a documentary.
stiiggy
Perhaps it was counterfeit. There are numerous episodes where they deal in counterfeit monies.