In the 50's and 60's, the players were paid very handsomely in comparison with average working person of that time. It's their fault for not doing something with their money other than spending it. As far as any players who lost their money to swindlers who got the best of them, welcome to the investment world of promised higher returns.
I guess not every player can end up like Roger Staubach, having a successful business career after the NFL.