I've been to sessions where the music was great, but there was so much smoke in the air I simply couldn't bear to go back. I can tolerate a little bit of smoke (i.e. a few smokers -- if I'm not too near them), but otherwise -- for me -- it's simply not worth the unpleasantness of enduring more than a little smoke, no matter how good the music is.

FWIW, I have a still-vivid memory from more than 10 years ago:
The break room where I used to work had a couple of tables set aside for smokers; these tables had special vents overhead to suck up the smoke produced so nonsmokers didn't have to breathe it.

One day I happened to be in the break room while the fellow responsible for maintenace & such was cleaning these filters. I looked at them; the ventilation slits had a slimy greenish-greyish-yellowish coating. "What's that?" I asked him.

"That's the deposits from the cigarette smoke," he said. "Smokers have this stuff coating the insides of their lungs."

I've often thought that an anti-smoking commercial along these lines might be most effective...

Cheers,

YY