C'mon man, nothing would happen. Nobody would do anything. Test one of them next time, you'll see that they are absolutely all fluff.
I had a guy try something at Gillette last time I was there (maybe 2014?) and I said very loudly "I have a GREAT IDEA!!! How about you put down the nachos and hit the gym for the next year and when I come back to this stadium next time I will sit in these same seats and MAYBE just maybe you'll have a chance, but until then SHUT YOUR FAT FACE". Stunned silence by said Mass-***** and the entire crowd around us died of laughter (most of them were Pats fans as well). No problems the rest of the game.