With Dish and Directv, the national channels (USA, TNT, HBO, SHOWTIME) are the same on there provider. Only the local channels are different. With cable, the same cable company will have the national channel (USA) as channel 123 in one city and it will be channel 456 in another city. Why? Wouldn't it be easier for a cable company to have the national channel assigned the same number across all their regions instead of having a different number for different cities?