It's easy to default to saying that people should take better care of their money, but it's not that simple. Sometimes, unexpected circumstances happen like a job loss or unexpected expense that a budget cannot happen. When the demand for games is as high as it has been since 2008, those season tickets are like cash vouchers.
Sometimes, it's not about budgeting, but rather smart investing. Some people I know purchase season tickets, go to the low demand games, and sell the tickets to high demand games like Seattle, Green Bay, San Francisco, etc. to either nullify the cost for purchasing season tickets or, in some cases, make money off of the deal.
I get frustrated when the fan ratio is lopsided, but at the same time, I get it.