I know that duirng the last few UK games when there was a gunshow, thye had the "command post" van parked out front with their large P.A. system making Orwellian states to those attending the games before entering that they would nt be allowed to have certain items on their person.
Personally, I got kick out of seeing the faces of the game-go'ers as we strolled throught the parking lot towards the building to head to the gunshow with our M4's slung. *LOL* The LEO's were cordial and very polite and would sometimes stop to admire our weapons (check us out). But never once did we ever have an issue with metro.