This is the whole point of the movie the Great Escape. The allied prisoners know they won't be tortured since they're in a Luftwaffe camp and not a Gestapo one.

This is the whole point of the movie the Great Escape. The allied prisoners know they won't be tortured since they're in a Luftwaffe camp and not a Gestapo one. After the escape, the ones who are recaptured are handed over to the Gestapo and are executed. Even in a 1963 film set in a Nazi POW camp, it was understood that there were rules. Sic transit.