PearlSLE wrote: the dealer said you just have to subscribe.
Did you get that in writing?
One thing I learned long ago about car shopping (after being told something by a saleperson that wasn't true) was to research the car(s) you're interested in. At one time that involved collecting brochures. Now, thanks to the Internet, rental car agencies and forums like this you can learn absolutely everything about every trim level and never be surprised.
While at the dealership carry a notepad and write down things the salesperson tells you like "yes, all you need to do is subscribe and that SAT button will start working". From your research you'll know the radio is actually just SAT 'capable' and not SAT 'ready'. When you're ready to start wheeling and dealing have the salesperson sign your notes certifying to what he/she told you. It can add some fun to the process and in this case you'd have probably ended up with the receiver being thrown into the deal. There's always a chance the salesperson will refuse to sign which simply means you shouldn't be dealing with them (or maybe that dealership).
Cheers