Another story happened to a friend of mine, also an American teenager living in Germany in the 1970s.

He was an excellent snow-skier, but evidently not such a good navigator, as he was skiing in Austria one day and took a wrong turn and ended up in a German town on the wrong side of the mountain without his passport (this was before the EU eliminated the need for passports at the German/Austrian border). He found a cab driver who agreed to take him back to his family's lodging in Austria. At the border, the cab driver reportedly made a simple wave of the hand to indicate to the border guard that my friend was yet another idiot skier, and he was passed through without any trouble over the missing passport.