I agree with most of what you say, but as you said, it's up to the organizers to make sure nothing goes horribly bad. And I just think that in the case of sports in a stadium, there needs to be 0 tolerance towards people breaking on-field. I agree it's never completely safe, and most of the time the sport itself is way more dangerous than the crowd, but the security team has one job, and in the case presented here they did everything they could, and that's the way it should be. 0 tolerance, since it can go downhill very fast.