You have a point, however... the conservative movement(and actually the liberal too) in this country is to privatize everything. Even national parks and grounds. In this country they have started setting up free speech zones. Places off to the side where a protest will have little or no effect.
This directly violates our founding laws. Check this out.
What they are saying is you have the right to protest. But you do not have the right to protest where anyone can hear you.