Cigarettes have a another purpose, other than just the act of smoking them, which I believe is a contributing factor in their popularity...aside from the whole addictive thing. They give you something to do with your hands while talking, and something to look at if you feel the need to avoid eye contact. Bumming them out is also a quick way to make friends. There's also tons of body language that only works if you're smoking.
Anyhow, the possibilities are endless. Go now, and become a cigarette master!