Your question made me wonder as well, so I went to IdeaWorks website and they note their client list as follows:

Our international client list includes the hotel, airline, marine, railroad, and consumer products sectors: AirAsia X, AirTran, Alterra Coffee Roasters, ATA Airlines, A.T. Kearney, Amtrak Intercity, Baboo Airlines, Baymont Inns and Suites, British Airways, Esprit Airways, EzRez Software, Flybaboo Airlines, Flybe Airlines, Forever Resorts, Fosshotel of Iceland, Frontier Airlines, Hawaii Superferry, Kalahari Resorts, Kwik Trip Petroleum, Lacek Group - OgilvyOne, Lake Michigan Carferry, LAN Airlines, Malev Hungarian Airlines, Marcus Hotels and Resorts, Marcus Theatres, Martinair, Mondial Assistance, Ogilvy One Worldwide, Pegasus Airlines, Radixx International, TransBrasil Airlines, Virgin America, Visa and Vueling Airlines.

Of course, this, too, could be manipulated.... but I really think the company is more inclined to want to be selling their more 'detailed study' book as well as some developed software. There actually is, on their site, a 2009 TATL reward study... equally as interesting.

From what I have seen about redeeming US awards, I honestly don't think they manipulated the stats too much in that direction.