Anecdotally, I majored in economics at a large public school with a (at the time) national championship caliber hockey team. All of the players on that team that made it to the NHL attended the same classes I did. Most did come from privileged backgrounds but at least one grew up in the projects of Toronto. The coach strongly encouraged his players to take at least a few classes that would give them some financial grounding.
In Canada it's different - our sports press is all hockey, all the time. Granted I don't pay much attention to it, but if any sports news makes it to my news feed, it probably is going to be about atheletes going bankrupt.
Any broke Formula 1 race drivers or tennis players? That's where you'd really look for athletes coming from wealthy families, I think.