I've had season tickets in past, and I even used to make sure I flew to Utah for at least one game a year before I lived in Utah, but never ever have I considered it my duty to buy tickets nor have I ever thought that my attending a game or not somehow impacts my manhood. We're talking about watching some kids PLAY A YEWTING GAME! Holy yewt, people, get some perspective.
If you really enjoy going to the games and make it a priority, good for you, that's awesome that you have a hobby you enjoy. If someone else has different priorities for their time (for many, going to a game is a commitment of at least 8 hours) or money why is it any of your business? If you're worrying that much about someone else's entertainment choices, it's probably time to re-evaluate your own life choices.
No matter what level of time or financial investment they make, I welcome anyone who wants to call themselves a BYU fan.