They need to get the college sports off of national TV and set up a farm team system. But that's a debate for another time probably.
The RedSkins can't fill their stadium in a major market. Try to get Alabama tickets ... or NotreDame ... or Penn State all in minuscule markets.
Years ago the Redskins always filled- they've just sucked for so long people find better things to do with their Sundays (disclaimer-am a fan from long time back).
The Patriots on the other hand now fill their stadium (I live in the Boston area now). They didn't use to do that.
So it may depend on how well the team is doing.
EDIT: Except for Tennessee. Those fans are crazy.