Being a fan's a two way street. Any relationship is. If your spouse turns into a money grubbing, unfaithful parasite, would you be wrong in finally walking away after many years of abuse? Most would say no.
Under certain circumstances I'll go. I'd like to be able to say I saw Strasburg at his peak. I have affection for many individual Mets players. If I'm given free tickets and have the time I'll go. Actually patronizing the team in any conventional way, however, sends the message fans are O.K. with the way they've been treated and how the team's been run. It invites more of the same behavior. As a result, it is wrong.
As a former plan holder, I understand that the routine becomes a way of life. Even around 1992-3, it was difficult for me to walk away - and that was one of the hardest teams to watch you could imagine. Still, you find other enjoyable ways of spending your time. As a former plan holder yourself, I suspect you realize these people do not offer value for money. In my opinion they do not value Mets fans as customers or human beings.
The only correct way to deal with any abusive relationship is to distance yourself from it.