We've been playing FCS-caliber football at home, have had two of the worst finishes we've had in years, have been losing consistently to in-state rivals and we still outnumber USU or Utah at home games.
Sure lower cost/some swag may bring in a few more, but it doesn't have even close to the impact that winning does. Start playing good football and people will show up in droves. You could admit people for free but if we keep losing to everyone it won't matter.