Many young men in the 1960s and 1970s came to reject some of the traditional ideas about manhood that many of their fathers tried to pass down - like unquestioning respect for authority even when that might mean killing and dying for questionable or unjust causes such as the Vietnam War.
The best thing I can say is professional football is a business. When they are recruiting football players, they are not recruiting model citizens. Everybody has to be aware of this. What's being selected for the NFL is the ability to play and perform on Sunday afternoons. Everything else is secondary.