Anyone can make mistakes, so a guy flying a 8kdollars plane could be shot down by accident by a modeller that simply cannot afford the expense... I guess that the guy that flys a expensive airplane should be ready to lose his investment at any time, by any means,
interference, mid-air, mechanical problems or plain pilot error. If he is "lucky" to be shot down by a person who can afford the mistake, i am sure that this person will pay happily ... but if the guy is poor on money or poor in honesty... well , there is nothing much to do.

Fortunately this kind of accidents are uncommon, and we better should focus in the main causes of r/c accidents like lack of pilot knowledge or mechanical issues.

Just my thoughts, Enrique