Seems like a booby trap to me, which is illegal. I suspect if one of these does enough damage there will be laws against it. The intent was to destroy - still I sympathize with the desire to have their terms followed, and I think this situation isn't that bad, but, I suspect there will someday be one that is pretty bad.

Except that shouting fire in a crowded theater isn't actually a crime at all and you can't be prosecuted for it (doing so would violate your first amendment rights). You can be at most banned from the theater. However, it's understandable people would think that it's a criminal act given that even prosecutors repeat this long-standing myth. Legal Eagle has an excellent video describing just how wrong this is and it's history: https://www.youtube.com/watch?v=jTsPgiUoBKA