The Magical Hotel Card is a meme/trope where a character hands another a card for a hotel he or she likes. The assumption being the visiting character's stay will be put on the tab of the host character.
These cards are generally handed out under the assumption the visiting character will make up a hotel, or that both parties are too lazy to make up a hotel or research one to visit. As such, The Magical Hotel Card is invoked when a character wishes to stay somewhere, and is handed a recommendation for an unnamed hotel.