I'm not, nor have I ever been, a regular smoker. I have, on occasion, smoked while drinking way back when I was a kid in college. In general, I find it to be a fairly disgusting habit.
However, if I found out I was turned down for a job because I was a smoker and then I did a little bit of internet research, yeah, I would contact a lawyer.
Smoker protection law
Do I think smokers should be protected? No. But as various websites suggest, employers do not have a right to discriminate against you. So, as I said in the post you quoted:
Sounds like a lawsuit waiting to happen.
And as we've seen, soooooo often in today's world, companies will settle, for a hefty sum, rather than go to court. Queue the cost benefit analysis.