I'd bet that's simply due to advertising. Advertising within TV is insanely tied to location, and we're just now starting to figure out online advertising. TV has country, local, regional, etc ratings and reach to judge ads and prices by.. i'm not sure how much, if any of that, is standardized by advertising.

It's written in the law too, mind you, so i'd be curious if online advertising ends up with some standards that providers have to adhere to. Ie, allowing regional ads, knowing the reach, etc.