Nope, no smoking ban at the Penguin. I do think that many of the "daytime" folks are families that aren't smokers and many smokers don't necessarily puff away at lunch. It is the later dinner/drinks, drinking crowd that will smoke before, during and after a meal
... (Used to be one of them before I quit, so no judgement here).
I have been to a few restaurants in Charlotte that are either 100% non-smoking or limit smoking to the bar area.