Anything large enough, like a stadium can eaisily become a concentration camp. Hell, when you think about it, for a few hours each day, at least one
stadium is a concentration camp...
Maybe thats their real purpose

.
It is kinda scary when you do think about it though. Thousands of hapless people in a single enclosed area...that's like an invitation for the NWO,
Alien Overlords, whatever to "come and get us", isn't it.