To an extent that is true. But these folks were also charged with obstructing a highway and rioting (which most likely means they did not have a permit). Both of those are far beyond just "saying and thinking".
Rights don't require permits, priviledges do. Free assembly is a right, not a priviledge. Constitutionally, it cannot be tied to a permit any more than prayer can.
I watched the video. It appeared they were on a sidewalk and not the road. Now were they staying in one place. The continuously kept trying to relocated and were stopped by 'parade attendees' with signs caging them in.
Did you watch the tape?