When you don't smoke for a year or so, that first one when you un-quit is unparalleled pleasure.
It's worth starting and enduring the pain of quitting just to be able to come back and feel that glorious mind blowing forbidden pleasure of the first one back. The power trip in not starting again is also delightful. I like having a cigarette about every year or so. A few times I quit, I was lured back, but I've only had one full cigarette since June of 2008.
Smoking is definitely not a good lifestyle for the long term. But as very occasional guilty pleasures go, it's truly top-notch.