I hate pretty much everything about smoking. That includes marijuana; it smells like skunks to me (plus I hate stoner humor, but that's neither here nor there). The smell of cigarette smoke makes me sick to my stomach. I don't mind clove cigarettes quite as much, but it gives me cognitive dissonance, because my brain goes "smoking = ew!" while my nose goes "cloves = yum!" XD
I'm not gonna get up on a high horse about how OMG SMOKING IS BAD AND YOU ARE BAD FOR SMOKING. Yes, you have the right to live your life the way you want, but so do I, and I want my life to involve breathing air that doesn't stink. Smoke if you want, just please do it somewhere far away from me. I won't necessarily think any less of you if you do smoke (I do have friends who are smokers), as long as you are considerate about it. And obviously, I won't date anyone who smokes.
Anecdote: I'm standing at a bus stop. It's raining. There are a bunch of other people at the bus stop, many of them crowded in close under the bus stop shelter to stay out of the rain. A guy right next to me lights up a cigarette. (It is, by the way, illegal to smoke at a bus stop.) Legality aside, I don't particularly want to breathe in his smoke, and I'm guessing at least some of the other people waiting for the bus don't want to, either. So I ask him, "Could you please take that somewhere else?" His response: "Fuck off."
...yeah.