I will never and I mean NEVER be able to eat a snow cone again at the ballpark after watching this video provided by Deadspin.
The good news is the guy was fired immediately, the bad news I am sure this happens a lot. So, my suggestion is never get anything from a vendor walking through the stands.
It is better to just get up and get your snacks from food stands, not like you have to worry about the Astros winning or anything.