As with what Lightages said, it sounds fair on paper to let the winner keep it, but if the draw was flawed he didn't win fairly. It was a competition with 4% of the entrants left out who were just as likely and some even more likely to win as him.
For me it sucks a bit being left out, for those who got a chance or didn't have a horse running it's easy to quickly dismiss it as tough luck, just saying I would have liked my chance.