I'll go first:
One time when I was a kid, I met some guy on the chairlift and introduced myself. I thought I was being pretty cool to say "hi" to people on the chairlift because no one ever talked on rides up. Anyway, we had a chat, it was his first time back on the slopes in a while, but he loved skiing and was about to go to college. Near the top he asked if I'd show him around some cool spots. We skied around together for a bit, and he was a decent skier, so I showed him some stashes and we dropped some cliffs together. I was so used to people being completely antisocial on chairlifts and not ever seeing each other again that this was mind boggling.
Never saw him again, but this changed my view completely about skiing because I thought skiing was an individual sport where you would ski with your friends from school or other sports, but nobody else.