See? There are options, just maybe not the options that are well liked!
Bear with me..
As Hemi pointed out, DirecTV is selling single games for $40-50. The only reason for that is because someone sued DirecTV and the NFL, and the NFL was forced to allow sales of single games because the packaging couldn't be all or nothing. Now that single games are allowed, you have the ability to buy what you want.
DirecTV is paying the NFL $1 billion for the rights to Sunday Ticket. It is in the best interest of DirecTV and the NFL to provide the full package or high-cost single games. It is in DirecTV's interest because it is $300-$350 for the full package, and they need about 3 million subscribers to take it to break even. Dilute the offering so that there are single team packages, and there will be less subscribers to the full package offering...
And the NFL wants the full package buys simply to keep too many people from subscribing to a version of Sunday Ticket so that their local television contracts aren't devalued. Imagine if that 3 million subscribers then goes to 9 million at a third of the cost. People won't be watching the games on their local channel, which means less eyeballs on the local game.
DirecTV and the NFL wouldn't offer single games if they didn't have to, by law.