First I do donate.
Your American Cancer Society is not a good comparison. If the ACS was competing against 20 other groups trying to cure cancer and the others were much better funded and making breakthroughs while the ACS lagged behind, then it can be argued that you are sorta pissing your money away giving to ACS. In any event, giving to a charity trying to cure disease is not remotely the same as trying to fund a football program trying to beat other football programs. One is helping humanity. The other is a sport.

Your third sentence hits the point. Fans want to see their program thrive. Whether its VT or any number of other schools. When the sport is set up such that its virtually impossible to succeed against the elite few then the donations are more or less being wasted. Thats the nature of whats happened to college football.

Think about pro sports. They put in a salary cap so that a team in say NY can't spend 10 times more and dominate a team from Pittsburgh or Tampa. The league would fail if two or three teams always dominate. College football is slipping down this slope. Its not good for the VTs of the world and its not good for the sport.