The New England Patriots have won more regular season games and playoff games than any other team since the Brady-Belichick era got rolling in 2001. Their fans have paid for it.
MSNBC recently pointed out that the Patriotshave the most expensive ticket price in the league based on the secondary market for tickets. Unlike some lists of this sort, the source actually has factual data to back up their claims.
There has been criticism of the Patriots crowd in recent years. Seemingly spoiled by success, they only seem to get "up" for the biggest of games. They are also quick to get quiet or turn on the home team if things aren't going well.
Perhaps the fans would argue that they paid a lot for those seats, and they expect a certain level of performance to match.