Well, we don't agree that a venue where people would get injured in a panic is sub-par. We've learned a lot since the 1910s, but panics are like hundred year floods in that it does not make economic sense to constantly prepare for every possible event of that level of unlikeliness.

But I agree that speech that is intended to cause harm but is unlikely to be able to cause harm (i.e. an obviously false claim that the popcorn is poisoned) is not a good candidate for criminal penalty. But it's generally quite hard to prove that one intended harm if one's acts seem unlikely to be able to cause harm.