Even a lot of people who agree with them on issues are going to be yelling, "shut up and play some music!"
The ones in empty seats won't be yelling anything.
That is kind of the problem I have with this bunch.
They can say what they like but to sell tickets to a concert and then turn it into a political harangue of the audience is kind of like being invited to dinner only to find out it is actually a candle-light party.
In this case it is at least they are up front about it. So a lot of people aren't going.
But when you sell a me a ticket for a concert, "Shut up and Sing!" Or beware the flying slushy. If I want leftest politics I can watch See-BS! for free.