Our Big Feet

http://www.sciencedaily.com/releases/2008/04/080428120658.htm

ScienceDaily (Apr. 29, 2008) — An MIT class has estimated the carbon emissions of Americans in a wide variety of lifestyles -- from the homeless to multimillionaires, from Buddhist monks to soccer moms -- and compared them to those of other nations. The somewhat disquieting bottom line is that in the United States, even the people with the lowest usage of energy are still producing, on average, more than double the global per-capita average. Whether you live in a cardboard box or a luxurious mansion, whether you subsist on homegrown vegetables or wolf down imported steaks, whether you're a jet-setter or a sedentary retiree, anyone who lives in the U.S. contributes more than twice as much greenhouse gas to the atmosphere as the global average, an MIT class has estimated.
...
While it may seem surprising that even people whose lifestyles don't appear extravagant--the homeless, monks, children--are responsible for significant greenhouse gas emissions, one major factor is the array of government services that are available to everyone in the United States. These basic services--including police, roads, libraries, the court system and the military--were allocated equally to everyone in the country in this study. Other services that are more specific, such as education or Medicare, were allocated only to those who actually make use of them.