It seems hard to grasp how any intelligent person could think smoking might be healthy. Just out of curiosity I once asked Ray if, perhaps, he thinks smoking might have some health benefits. His answer was: no. He said nicotine has some good affects but inhaling smoke of any kind is extremely toxic and carcinogenic.
I could see smoking being a net positive if say, one was rolling his/her own cigarettes, and good quality tobacco without added toxic compounds, in an environment with pure air, like a house in a countryside. That could end up being very relaxing, and the toxic effects of the smoke might be compensated by the beneficial elements, nicotine and relaxing effect.
A lot of centenarians and old, healthy people, seem to be smokers and drinkers, typically it's just a little like 1 cigar a day or a pipe or a few cigarettes, along with a drink or glass of wine.
In the modern environment with already high existing indoor air pollution levels, smoking a pack of commercial probably doesn't help at all. Moreover, most of the smokers I know don't really get to relax while smoking their cigarette, they just smoke through a stressful lifestyle.
So I think context is important. I think Travis was living in a rural environment, and probably had a laidback lifestyle, so maybe smoking was beneficial for him.