I am very against smoking (and I'm from a tobacco state), but...

I think this is wrong.

Hospitals Shift Smoking Bans to Smoker Ban

and as the article states, this is why:

One concern voiced by groups like the National Workrights Institute is that such policies are a slippery slope — that if they prove successful in driving down health care costs, employers might be emboldened to crack down on other behavior by their workers, like drinking alcohol, eating fast food and participating in risky hobbies like motorcycle riding. The head of the Cleveland Clinic was both praised and criticized when he mused in an interview two years ago that, were it not illegal, he would expand the hospital policy to refuse employment to obese people.

“There is nothing unique about smoking,” said Lewis Maltby, president of the Workrights Institute, who has lobbied vigorously against the practice. “The number of things that we all do privately that have negative impact on our health is endless. If it’s not smoking, it’s beer. If it’s not beer, it’s cheeseburgers. And what about your sex life?”

Smoking (and dipping, which is even more disgusting in my book) are filthy habits. Smoking produces carcinogens in the air and aggravates asthma. (I am very sensitive to cigarette smoke, and would almost certainly not date a smoker, because this is my preference.) But, I also realise it's a powerful addiction, that people often must try to quit many times before they succeed. And even then, it's tempting. My mother quit for six years before starting back again, for example.

That being said, although I am very much in favour of bans on smoking in public and don't think people should smoke around their children, refusing to hire people, firing people for tobacco use, and testing employees for nicotine goes too far. It is a drug, yes, but a legal one. Unlike illegal drugs and other legal ones such as alcohol and prescription drugs, it's not going to cause potentially deadly accidents that will affect others, impair judgment, or incite violence.

Some companies even ban nicotine patches, something people use to try to kick the habit. How is that productive? What if a person smokes for 30 years, then quits a couple of months before being hired? Isn't their health also in jeopardy?

Where do you draw the line in terms of trying to keep down health costs? What about obesity? Diabetes? Multiple sclerosis? High blood pressure? Depression? Does that mean only svelte young people with no health problems or medications deserve to work? Do the rest of us just go on disability or welfare and strain the system further? Shouldn't those be reserved for people who really need it, rather than people willing and capable of working?

It's a complex issue that seems to make a certain amount of sense, at least in a pecuniary way, but really is a slippery slope, and I agree that discrimination of this type should not be allowed.