Yes, there is a time and a place for dissenting ideas and voices. What if I went to a concert in Carnegie Hall and stood up in the middle of the Tenor solo and started yelling. "Hey, I want more rock music! Why don't you let Led Zepplin play here?"
There are times for voicing opinions. In the middle of someone else's speech or performance is not one of those times. Sure, go outside. Hold your signs. Hold your peaceful rallies. I'll support you (and probably walk past you). Write your letters to Congress. Voice your opinion about climate change. But be respectful. Can you loonies do that?