Yes, when I was back in my hometown, visiting my parents, I saw someone at a tram station who could have been a classmate. But before I decided wether to ask, my tram arrived.
Even worse - the opposite: On a class reunion, I did not recognise "that old person there" - who turned out to have been a rather pretty girl once in school days...
Have you ever been shocked about the development of a classmate after years after school? (A few details too, please.)