In high school I occasionally smoked, and in college I did the "smoking while drinking" think. Purely optional both times (that is, I could go weeks without smoking then I'd have half a pack in the evening). It was basically just something to do.
After getting married I smoked a pipe for a while. Pipe smoking is drastically different from cigarette smoking (and as much disrespect as cigarette smokers get, pipe/cigar smokes aren't even allowed in most places; I can't speak for cigars, but while a pipe can produce more smoke than a cigarette, pipe smoke can also be much nicer smelling.)
My perception of cigarette smoking is that it increases stress rather than decreasing it. Pipesmoking, on the other hand, does decrease it--there's a lot more to it than flipping open a pack and flicking a lighter. if you're stressed, and you start a pipe, by the time you get the pipe going well, you're likely to be less stressed. The very actions in building a pipe are soothing. There was a study from the Surgeon General that said pipe smokers live longer than non smokers (and of course longer than cigarette smoking). Though of course there are health hazards to balance out the psychological benefits.
After my son was born, I quit smoking anything.
As far as I'm aware, cigarette smoking has virtually no benefits other than satisfying an addiction (which wouldn't be there had the person not started smoking). As has been mentioned, drinking in moderation (one glass of wine or a one beer or one mixed drink a day) does have some health benefits (again, you have to balance that with the potential health risk, but the risk/benefit is different for each person.)
I will say this, when I wasn't smoking, I could rarely stand to be around smokers. And I hate going places -bars, concerts, casinos, etc.--that are heavily populated by smokers.