You're saying that the transportation conditions aren't quite the same. Horses transported for purposes other than slaughter are supervised and have more space. You spoke of race horses, and I gather that measures have been implemented.
This raises two questions. First, wouldn't the best solution simply have been to make the conditions for transporting horses destined for slaughter more like the conditions for race horses?
Second, when a horse is sold for purposes other than slaughter, but not for racing, what are the transportation conditions?