If you went by that logic, then cable and Dish Network would both carry them across all of the MLB territory. There are rings of service available for a price. As a provider of services, Dish/DirecTV/Cable can decide how many rings of service they wish to provide. In the case of the Giants, DirecTV has decided that they will pay the extra price for the rights to broadcast the Giants RSN into Oregon. Comcast has now split the Giants and A's into seperate RSNs. DirecTV has decided not to purchase the rights to broadcast the A's into the ring (Oregon) that contains the A's. You will also notice that they will broadcast the Giants/DBacks/Dodgers and Angels into Las Vegas, but will not broadcast the A's into that market.
Please go here:
Local Regional Sports Network Information : and insert a zip code of 89121.
Again..it's all about money, and nothing else. Don't try to throw logic (I'm 500 miles away from the stadium/MLB says I'm in the area/I'm blacked out on Extra Innings and MLB.TV) into your argument. We are talking about rules that are written to achieve the most dollars into the pockets of the MLB.