I hope the guy wins. Fat non-smokers cost a lot more insurance wise than thin smokers. They get hypertension, diabetes, heart disease, cancer at high rates. They are discriminating against him specifically because he does something the company "doesn't like", while "allowing" other higher risk off-duty activities like unproteced gay sex. I hope his lawyer points this out.
This guy was not singled out. He was given a year's notice along with everybody else. And the offer to help him quit.
And don't worry I'm sure Scotts will be going after fat people next. If it's legal and they can get away with it they will.