Sort of stupid. It actually costs money to eat healthy, which many people can't afford in the states (fresh fruits and vegetables, grocery store far away, no car, just by crap at the convenience store then).
The US doesn't compare well to Europe on quality of life for those not in the middle class. Ya, they can afford some crap, but not what they really need to improve their lot (decent food, decent education, healthcare...). The libertarians don't really get that, and think everything is peachy perfect in the states (except for too much socialism).
Of course, one could always hit the gym...if they have enough money (or just move to California and ride a bike everywhere...if they have enough money).
http://npc.umich.edu/publications/policy_briefs/brief28/poli...
This reminds me of Medicaid in the US. Something like 20% of the uninsured in America are actually qualified for free healthcare, but don't enroll.