A weighty issue

I few weeks ago, I actually wondered how long before I saw a headline like the one of Reuters today:

Obesity Contributes to Global Warming

I'm not inclined to completely disagree, but I would question this particular study and its validity. I take exception, especially, with the notion presented that those with a lower BMI use less fuel because they walk more... I know PLENTY of people with a BMI under 25 (which is the widely accepted value for outer limit for healthy weight) who spend 20 minutes driving around a parking lot to park 2 spaces closer to the entrance... or those that are appalled by the notion that I would walk to the grocery store or post office rather than drive (it's a half mile).