Keeps you warm on cold days, lol. ***. A lot of people try it because they see others doing it. Usually that's from those that start at a younger age. The oral fixation is very common, linking that to it being a stress reliever to some. That's probably the most common excuse. Then they don't quit because it has become an addition or a (bad) habit.
It's disgusting though. Smells nasty, tastes nasty during and after. By after I mean, have you ever kissed someone after they've smoked? Blech! Terrrrrrible.