Honestly, it's the danger to the horses I have the problem with. I know many horse sports are inherently dangerous based on principle, but most of them are pretty damn safe. Jumps racing seems like one of those unneccessarily dangerous ones that I don't know about. Like you said - the people at least choose to participate. The horses have no say in the matter, and when it's so likely for them to get injured....
RE: Broken legs, despite what you might hear are still not as fixable as you'd think. Fractures, maybe, but a horse can't "lay on its side" for 6 months, it'll get compression injuries and die. A sling is not great either because of the huge potential for crippling hoof problems (founder, laminitis) that arise from the three hooves overcompensating. Mostly a leg break = a dead horse. The saying "A downed horse is a dead horse" still rings true!
I guess that's my main issue. I don't think it's worth it to put the horses up to that much risk, I do not see it as fair to them. there are negative asects and bad people in EVERY horse sport, but some go beyond. I am glad that the horses are shown compassion when they are hurt, though - Some of the things I was privy to at the racetrack here were downright coldhearted. Like I mentioned, I do not know enough about jumps racing to have a true opinion on the matter yet, and once I am on a good computer I will watch the posted videos and do some digging! Horses are definitely graceful animals to watch, and watching them do something like jumping can be incredible! I am definitely interested in learning moreI feel like this will start one of those black holes of the internet where I watch one video, and keep clicking related videos and get sucked in and then realize several hours has passed.
The one horsey sport I really want to try is mounted archery. I have been trying to save for a bow for AGES, but as a starving college student every time I have the money there's something more important it needs to be spent on, haha. So, I have to content myself with videos.