Perhaps nobody dies from secondhand Big Macs, but there goes that argument that non-smokers use about how they have to foot the insurance bills for smokers. You'll be footing the bill for the fat guy, too, but nobody yells at complete strangers about over-eating.
Obese people get charged more for insurance, smokers do too. It should not affect a non-smoker or non-obese person's premium.
It's all bullshit in my opinion. If anything, they should be charged less, because they're going to fucking need it.
I always answer no when the doctor asks me if I smoke/drink/do "street drugs," all consequences put aside.
(What the fuck is a street drug, anyways? They sound absolutely retarded when they say that shit.)