said by jjeffeory:
Yet DC doesn't have Fios... Maybe that's one reason why there are caps there?
DC area includes northern VA and part of MARYland. Several million people. The Distict of Columbia itself only has several hundreds of thousands of people. The majority of people that live in the DC area live in Virginia and MARYland.
And both of those areas have a high penetration of the FIOS footprint.