heh...I'll do you one better:
Fuck the Boston Tea Party, the American civil war, the United States Declaration of Independence, your Constitution etc.
People like you belong under the rule of a monarch if protesting bothers you so much.
I'm just trolling bro, people can protest all they want so long as they don't violate the rights of others.
For the record, i'm not a fan of the Boston Tea Party. It was a protest that currently would be illegal under the Constitution anyway. Freedom of Speech doesn't entitle you to the destruction of private property, no matter how pressing your point may have been.
I don't understand your American Civil War comment. Unilateral Secession is illegal under the constitution.
The problem with meetings like this is that the protestors aren't unified under a single cause. It's a variety of groups, protesting about a variety of different things and invariably some pissed off protest group goes to far and pushes the police's buttons.
Then all hell breaks loose.
And of course they sometimes hold the event in areas with police forces of questionable characters.
There is an expectation of violence at these events (unfortunately) and I wouldn't be surprised if that was the intent of a couple groups in attendance in order to further their own cause.
PS: I'd remind you that Hate Speech is illegal in your own country. So much for freedom.