Let them carry on. I like the fact the only message their demonstration gets across is that they are minority group of knuckle-dragging goons which no one gives two hoots about.
I know what you mean, but some poor copper risks having his jaw punched, some poor business owner risks having their window put in and some passerby risks being the victim of affray. Sort of had enough.
Perhaps it's time to invite another council in England to hold the march.