when you book through orbitz/travelocity/expedia you are charged at time of booking. when you actually get to the hotel and check-in, your reservation typically does not have your credit card info on it because the 3rd party (orbitz/travelocity) sends your reservation w/ their own credit card (typically a mastercard). they have a negotiated rate hotels charge them for these bulk discount rooms and the hotel is allowed to charge their credit cards for room/tax at that negotiated rate only. typically, the guests are not supposed to see the final room/tax bill because the rates on the receipt are different from the rates they paid (i.e., if you pay $100/night on yoru visa through orbitz, the actual stay is like $65/night and charged to orbitz mastercard). This is how they make money on hotel stays. If there is a problem with your room, that is why you have to go through orbitz to seek any refund because the hotel never charged your card in the first place.