yes but with a cell phone that additional phone has it's own number / line.
Neither does DirecTV. The 6$ fee is for the programming that is shared, which is why your primary reciever is free and the fee is charged whether it's leased or owned.
It's not different than the cellphone service you speak of, where they do family plans. You pay full package price on the primary phone and each additional phone is 5-10$ to share the minutes.
Same with DirecTV. You pay the full package price on your primary reciever (why it's free) and additional 6$ for every other TV to share the programming. It's also why you still pay the 6$ on C31 clients, because it's not for equipment. It is for the shared programming.
and when the box rent price and the mirroring price for owning the box is the same that makes it hard to work out and some of it is a cash grab.