This is difficult to understand, frankly. For one earning so much, risking it all for $200k feels irrational. Though sometimes greed, poor sense of judgement, or pressure from the wrong source fills a person's sense of risk. Some athletes also get caught up in pride or boredom, with the feeling they can't be touched. At the end, the example appears to be a sad one of how a single bad decision can wipe years of hard work.
Everything you have said is probably what's in the mind of these athletes when they do such actions. They feel untouchable or they really are willing to risk their careers for these bets. Because there's this sense of satisfaction when they do that. A gambler's mindset as they say and they'd do anything for them to win and maybe, their careers are boring and they don't want it anymore and so they let themselves to be part of the ring of the gamblers and for them to be part of it, they need to sell their actions and predict it as if they're able to know what they're about to do.
