The only question that matters is whether paintball shootdowns are unreasonably dangerous. The ones I've participated in aren't, and I've never seen any evidence to the contrary. Certainly a picture in Model Aviation of a crashed plane is not evidence of any such thing. Sure, the planes will sometimes crash. But that doesn't mean they are likely to hit spectators. The fact that people are intentionally trying to hit a plane is irrelevant, because it doesn't make the activity unreasonably dangerous. You concede this yourself when you say it's OK to do this with foamies. Car companies crash cars with dummies in them every day. Should they stop because these crashes are "intentional"?

If you don't want to do this sort of thing, by all means don't. But please don't tell me I shouldn't do it unless you can come up with some sort of evidence. Saying "definitely" is not evidence.