The thing is, if you want to create havoc, when inside the sports arena it's really big and seats are spread out. You could do a lot more damage out there amongst the nose-to-nose crowd crammed together trying to get inside through the security gates. Same thing goes for airport security. How many people on a typical plane? 200 maybe? How many standing in a crowded mass of people waiting to take off their shoes and display their toothpaste to make it through security? 500? 1000?