Oh sure they do! Never had something serious but back in 2011 when I a drum lesson, the teacher accidentally hit me with a 7A kind of stick on my lag and... it stung a lot. Now imagine that done to the head...People are litigious!
A while back, now, I went to OzzFest at Alpine Valley.
Going in, we were told "You can't bring that in".
We told the guy...It's just bottles of frozen water.
He told us "Not the water, the blanket".
Apparently some folks were doing the "cutie-pie blanket toss" at an OzzFest and the girl went up, up, way over...crash.
And they sued OzzFest.
I can't see how (or if) a court could find the concert at fault in that instance, but they didn't want to take the risk.
We added our blanket to a "taller than me" mound and went in with our frozen water (potential) projectiles.
I could see a drum stick really hurting...possibly.