I don't want to start a whole dramatic scene, and I agree with a lot of the points stated above, however...I have to speak up and say something about the racing part. You even stated in your post that none of those disciplines were natural to a horse if they were out in the pasture...the only one that is, is racing. Horses in the wild run, it's the most natural thing for them. Therefore, racing would be one of if not the most "natural" discipline.
Now, i'm not trying to start chaos or specifically argue your points, and some of them are correct, but it's not fair to say they're all treated cruelly and abuse and thrown away. That's nuts. Most of those horses on the backside are treated better than any people back there, or better yet, horses anywhere else. This really bothers me, just like the usual "TB's are crazy" stereo-typical statements. And "TB's aren't trained"....just because they aren't trained for the discipline that you bought them for off the track, certainly doesn't mean that they aren't trained. They are very well trained, for the racing discipline. Where else will you find such well-broke 2 y/os? These horses see chaos and crazy / scary things every day. They really are broke to a lot. Anyway i'm getting off track here, back to my point. Most of these horses are treated very well, get very well groomed, cared for, their legs are done up every day, etc, etc.
Don't get me wrong, just as there is in any part of the business, there are animals that aren't treated like they should be, and some do end up at the sales, but not like they make it out to be. This is infuriating to read, when i've been to numerous QH farms they believe in the "Submission" training, and keep them tied up for hrs and hrs on end, same with polo ponies, and many others. I've seen many other breeds at the sales, but still yet, people for some reason want to focus in on the TB's and rant an rave and give the racing industry a bad name. Yes, unfortunately sometimes horses have fatal injuries, but as many horses that run and as many races that are run on a daily basis in this country, it's minimal. There are a lot of rules and restrictions on horses able to run, drug rules, etc, etc. Just as much as there are unfortunately fatal injuries on the track, there are horses starving and having fatal injuries on the farm. Another thing, when horses are injured or have a bout of colic or anything like that on the track, you almost never hear of the owner putting them down, unless they have exhausted all other options. You almost never hear of an owner that wont do surgery for colic or to remove chips, etc, etc. On the other hand, you hear it all the time for simple ranch horses that they think just don't deserve the money wasted.
I understand there are some things in the business that aren't right, but I felt as though I needed to somewhat defend it, because some of those points quite honestly just weren't fair to say.