I was a Pan Am 727 Flight Engineer waiting for start clearance in Munich, Germany. I was listening to the radio since I was the junior crew member. This was the conversation I overheard:
Lufthansa (In German): "Ground, what is our start clearance time?"

Ground (In English): "If you want an answer you must speak English."

Lufthansa (In English): "I am a German, flying a German airplane, in Germany. Why must I speak English?"

Beautiful English Accent (before ground could answer): "Because you lost the bloody war!"