I think you’re seriously stereotyping D1 football players. About 25% are walk ons so they obviously got accepted into the school and are willing to pay to be on the team. Any expectation of playing in the NFL for most of them lasts about one day in D1 practice when they realize they are just another guy buried deep on the depth chart. About 5% of the 10,000 D1 players get a chance to try out for an NFL team.
What about all the NFL players that are set for life? Cam Heyward, TJ Watt, etc.? Are they also foolish to continue playing? Seems a 22 year old with limited earning potential otherwise would have more reason to play for $70k than NFL stars who have already cashed in on their second signing bonus.