But a horse with a good career can bring in money for years.
Just because it is raced at two, does not mean that that will be its only year racing.
Have you ever walked on a TB track Jumpehunter? Its can be tough walking because its several inches deep for *gasp* cushion! A Standardbred races on a much harder racing surface then a TB. There is a reason the TB tracks close down in the winter in the northern regions...because the footing is not good enough to keep them racing on all winter. That's when it becomes too hard.
Show me a big winning colt that has been kept racing for years. How many US triple crown winning colts were still racing 2 years after winning the Belmont? Even one year after taking the triple crown? These are colts that can obviously win big races and take big purses. If it's not damaging them and a significant risk to their physical well being then why stop racing them. They can race and still be used as breeding stallions. They'll bring hom more money that way.
That fact is that the damage is being done and the risk is significant. So they are taken out of racing because they will have a much longer and profittable life being used for stud. If they keep racing them they could at any time (racing or training) end up like Barbaro. It's only geldings and fillies that are kept racing if they are winning the big purses (and of course they can keep racing winning small purses too as long as they're profitable).
As a percentage, how many horses (especially colts) have a career beyond 3 years (6 year olds) vs those that don't make it racing until 6. A 6 year old that is conditioned and not damaged can run faster than a 3 year old, so it's not about speed. An attrition rate of about 5,000 TB a year is not an insignificant number.
And there's a reason why tracks in the South and CA stay open in the Winter. They can keep making money, even if northern tracks can't.
The condition of the tracks has nothing to do with the fact that young horses are going to be damaged because racing, and the hard training needed to win races, is damaging to joints that have not hardened. Track conditions can contribute to it, but it's like saying it's the vinegar poured on the open wound that is the cause of the pain, not the lashes that created the wounds.
Horses spend the first 5 years of their life with their joints developing and hardening at different stages. Only a very few of the lowest joints are hardened before birth. People can understand about a babies skull still needed to harden before you put pressure on it, but they can't seem to grasp that horses need time to have their joints harden too. Just because they are not quite as fragile as a human infant's skull, doesn't mean that stressing these joints before they are hardened doesn't do damage.
Believe what ever you like. You can read information on training horses that's hundreds of years old and man has known for a very long time that horses should not be stressed that young. TB racing has worked hard to make people believe otherwise. Since most people don't really know about the developement rate of a horse they don't realize how much BS the racing industry puts out. If they were right then events, actions and the equine medical communtity at large would support what they say.
The rate of injury, number of horses processed in and out of the industry annually, the attempts to white wash-justify and explain away, and the factualy developement rate of a horse all point to an industry that is much like the tobacco industry of the last century. They want to make "their truth" what people believe. A lot of people believed what the tobacco industry put out. I know some who still believe it.
Don't look at reality in the TB racing industry. It's a dirty business. And if you do look and get tired of what happens to the horses.....look at what a some jockeys go through to meet the weight requirements. But at least they are people, who have the ability to decide for themself is they want to damage themself.