Ermm, as per the quote from the swimmer (below) I think it's more to make themselves richer...
"Proud, who won the silver medal in the 50m freestyle at the Paris Olympics in 2024, is hoping to break the world record using performance-enhancing drugs and win a million dollars on Sunday.
If he wins the race but doesn't break the world record, he will still make $250,000 (£185,000).
"There's no money in sport," Proud told the BBC before the games. "I was 30 and had just come off a silver medal, what future path do I follow?"