It's an interesting metaphor - and the theatre one is an apt one, but I make one tiny distinction. I don't see this as a theatrical play or a musical - I see this closer to a stand up comedy routine. Perhaps that's just me though.
When a troll shows up, I treat them like a heckler. That means there's extra entertainment to be had. As you said, most trolls are suffering from digital insecurity. We can choose to ignore them, but I think it's far more fun to let them make a fool of themselves. I think part of the fun of Medium is the difference between genuine good-faith disagreement - and allowing idiots enough rope to hang themselves.
In short, I believe in chucking the vegetables back; I don't want to ignore the veg or pre-screen who is allowed into my shows based on whether or not they're holding veg. Alison and I disagree on this - but that's fine, that's what a pluralistic platform is all about. :o)