It's a very old formula. Wins = you can raise prices. People don't want to pay for garbage, so if you put garbage on the field you have to cut prices to get people to show up. Put a winner on the field, however, and suddenly people aren't so worried about getting a good deal. During the 90s there was 80,000 plus week after week. Back then the ticket prices weren't so ridiculously low in comparison to the rest of the NFL.