I haven't experienced it yet, but I'm sure smashing through trees at speed isn't to fun either.
I've known a few that have crashed on our hills in one form or another.. The most recent in my memory was a Nissan 350z fully track prepped BIG $$$$$ car, going off the hill BACKWARDS at the finish line, at full speed striking quite a few trees a good 20-30' off the ground and a barrel roll or two until coming to a rest completely and insanely demolished. That was two years ago now... Last I heard, the driver was still in the process of recovery.. (haven't had an update in a while)
We've had some serious, serious injuries, and a few fatalities... but, it's all part of the sport I guess. You could break your neck getting out of bed, doesn't mean ya have to stay in it!
If you'd like, or anyone would.. I'll dig through Youtube and find some wrecks of the hills I've personally been on.. I've come close to wrecking a few times, but haven't got bit yet (being the key word)