First off, sorry your GameStop didn't have a poster to provide for you. As a Manager of a GameStop, we honestly sometimes don't even get the pre-order bonues on time, especially from Nintendo. We get a bad rep because of Amiibos but quite frankly as mentioned, more often than not we get shortend on our supply. I had a store in my district not receive any posters for their customers.
Most stores get sent games/items based on their pre-orders. My store had only 5 pre-orders for Happy Home Designer...and we only got 27 packs of cards....it's the same with Amiibos. Most customers think pre-ordering isn't important but it helps but again, sorry you didn't get your poster. If you had come to my store, I would of called another GameStop to find you one. Not all GameStops are crappy like everyone thinks they are...