They make it seem like you will walk out with a charge plate but then they've never had any in stock so they order it and don't say when it will be in.
Bait & Switch: Promising you an item for a certain price, then saying that it's not in stock (it never was) and selling you a different item for more money. You could also define it by a company offering you a free accessory with your purchase, such as the charging plate, but then telling you at the point of purchase you needed to buy a ton of other accessories at a huge markup to get that free accessory.
Nope, this was just out of stock. Guarantee that when you go to buy a 820 or 920 in a month, you'll get the charging plate in store.
That being said: If you got your phone in store or over the phone, and the charging plate wasn't listed in your order, CALL AT&T. You have to manually add the accessory to the order, and the rep probably forgot. Happened to me too.