True, but they also use it by the gallon in a simple cooker. Apparently using Heet is part of the rules of the race for safety reasons and is supplied at the rest stops-
http://www.iditarodforums.com/viewtopic....ac&start=10

http://www.arcticrecreation.com/gallery/v/iditasport2008/IMG_0552.jpg.html

http://stores.adanacsleds.com/-strse-Alcohol-Cooker/Categories.bok

http://vicariousliving.wordpress.com/2009/02/04/how-to-make-a-dogfood-cooker/

As you can see, these are just giant versions of a soda can stove, the important word here being "giant."