If one of the kids in your area decided to play baseball in the street in front of your house and the ball go through the windscreen of your car, do you just shrug it off and pay for it yourself or would you expect his parents to cover that cost? Or if its your 50yr old neighbour that strikes the ball, then what?
Sorry I didn't answer your questions, but I thought it was clear with my examples.
If kids play ball on a street and there parents let them, before anything happens I would call the police and have it stopped. Now, if a kid breaks the window, unintentionally then I have no choice but to fix it myself. But back to the first thing I said, I would try to
prevent this by walking out asking them not to play around parked cars etc. If they continued I would confront the parents then the police.
If an old man hit the ball , then I would ask him to pay for it keeping in mind I asked him not to play around parked cars, if I didn't speak to him before it happened then I guess he would have to repair my window. If he refuses then I would take him to court.
After all he is an adult and should know better
Back to the SHOT DOWN SCENERIO.....All RC flyers at a clubs field don't know better and can't pay for $10000 planes. So I hand it back to you , the choice is yours, fly knowing this and suffer the consequences or just find some where else to fly which suits your style of aircraft. Whether $1 or $10000.
I sure wouldn't fly a park flyer in a park with 20 other park flyers trying to do there own thing.