It takes an insane person to take part in any kind of armed demonstration. I was always taught, and I think most people are, that you don’t display a gun unless you are prepared to use it in self-defense, not to go out looking for trouble.
So now you are saying that a person is insane if they want to protect themselves when they demonstrate. Do you think with Antfia, bLM, and leftist rogue three letter agencies that it is safe to demonstrate if you are a Trump supporter? Perhaps you haven't notice the Trump supporters that have been assaulted leaving rallies/demonstrations.
We have a right to protect ourselves where ever and when ever. We should not abdicate that right under any circumstances because those places become killing zones, not gun-free safe zones.
By the way, do not assume that people who arm themselves go out looking for trouble. And for your education, there is a difference between brandishing a weapon and displaying a weapon - better known as open carry. That is still perfectly legal in Pennsylvania. No permit/license required. (Which are also hideously stupid. Criminals do bother to apply for one, but law abiding, hardworking Americans have to in most states.)
One other thing. There is a reason the 2nd Amendment comes after the 1st Amendment. It insures that we still have all the rights given in the 1st Amendment. If you haven't noticed lately, a whole hell of a lot of our rights are gone.
Sounds like you are willing to trade freedoms for safety and you will get neither.