From a comment to a recent blog entry:
"'Approximately 60% of the fuel is burned to provide climate control for Marines and equipment deployed at some 300 sites across Afghanistan.'"
"'It’s even funnier knowing that for this fuel to arrive, millions and millions are paid to local warlords as “road protection money' in a mafia-style protection racket."
"found/via this isegoria.net entry"
And this historically not a unique situation.
Consider that during the Normandy Campaign  and the Battle of France  that allied fuel & supply situation acute and absurd even noted so at the time, efforts to remedy same counter-productive. Consider that:
* "the number of divisions required to capture the number of ports to required to maintain those divisions is always greater than the number of divisions those ports can maintain."
* Aircraft transporting fuel to those units closest to the combat using "one and one-half gallons of 100-octane [AVGAS] gasoline to deliver one gallon of 80-octane motor fuel to the forward depots."