I remember reading last season about someone chunking their drink at an OF who talked back and it only takes something like this once getting noticed to ruin it for everywhere.
I don't know about last season, but I know that already happened once this season against Purdue. If I remember correctly, the Purdue RF was diving for a ball and missed, and while most of us in right field were laughing and heckling as he got up and ran to the ball, one fan threw his drink at the player. Said player got the ball, made the throw, then charged back to the wall and yelled at the fan and when the fan got a little too close the player tried to punch him (the fan ducked back and the player just hit the wall).
It shouldn't happen at all at any point in a season, but we definitely don't need anything like that happening this weekend.