I think the latest expansion may have tipped the supply/demand scale. Actually, ever since the north stadium expansion, I have never got the impression that getting into Memorial Stadium was tough or crazy expensive, even for big games. What I would like to see them do is work on making the stadium more comfortable. Widen seats, add seatbacks, widen aisles so my knees are not jamming into the guy in front of me, ect. I think if they got capacity down to around 78k- 80k, you would see Memorial become a tough ticket again.
Another thing that has changed in the past 20 years is every game is now on TV and in HD. To think that does not have an impact in demand when you consider the total cost of going to 7-8 games a year you are kidding yourself.