I just got done rebuilding Crow's nest at Brickworld. Came back to the table to find it shattered. This is why we can't have nice things.
Edited to add: Turns out the cleaning crew bumped the table. They let the convention staff know, and they passed along an apology when they saw me.
An accident like that is completely understandable - it's much better than my suspicion that it had been some stranger playing with the model, breaking it, and then sneaking away.