There's a saying that football is a gentleman's game played by hooligans, and rugby is a hooligans game played by gentlemen. One would expect that when football fans arrange a demonstration, things would get really bad.
But now Inspector Gadget reports that where "intellectuals", students, make a demonstration, the actual outcome is violence and destruction, and the whole place is a wreck with weeks' work of cleaning up. When the English Defence League - basically a really scary-looking bald-headed islamophobic bunch of football hooligans - arranges a demonstration, they can be kettled and policed and, surprise, now one is injured, no one is attacked, and the place is spotless the moment the demonstrators leave.
It's all about what you want to do. The police tactics in demonstrations do not cause violence; the demonstrators do - if they are violent.
Alas, the most impressive thing about this demonstration is how quiet the mainstream media like BBC is about it. Somehow it isn't news at all that thousands of hooligans go to a march and no one gets hurt.