In all my years of wargaming, I have seen only 3 players throw a real tantrum: 2 ASL players who did so on a fairly regular basis and one player who took a PanzerBlitz loss really badly.
I've played maybe 200 ASL scenarios up until I quit in '94 and thought there was a higher percentage of ASL tournament players who were a bit special when compared to other wargame tournaments. Nothing close to the weirdos I saw at chess table, nobody waking up during a game and peeing on the board for example - but there were more players on edge than any other wargames I played.
And yes, the chess incident did really happen and I am just glad it was not on my board.