Both San Francisco and Changi airports are rolling out retail incentive programmes for their passengers this month.

San Francisco is issuing what it calls the SFO Passport which offers discounts and gifts with proof of purchase until January 3 at the airport's 35 retailers, food shops and also with some airlines.
Meanwhile, Changi Airport has launched a Christmas shopping promotion entitled ‘Double Your Joy’ which consists of a lucky draw where one lucky passenger will win both a Volkswagen Beetle car and a Volkswagen Beetle Cabriolet car. Entry to the draw is subject to the purchase of two items from any retail shop using Mastercard, NETS (Network for Electronic Transfers) or cash, from now until December 31 2005.
In line with its increasingly imaginative promotions, Changi Airport has also introduced a special display of selected merchandise at Santa?s House, located in the departure/transit area of Terminal 2, to provide shoppers in a rush with gift ideas for Christmas.
All purchases come with complimentary gift wrappers and a free gift wrapping service is available for purchases of S$100 ($59) or above.