Many times I have taken a smoking room becuase it was where I wanted to be, e.g. exec floor, and the room had no odor. I always check it out if there is no non-smoking alternative.

As to your friends who take a N/S room and smoke outside of it, I was under the impression that the halls on a N/S floor were to be smoke free, as well. I think that it is quite obnoxious for them to spread their smoke to others who choose to be in a smoke free environment.

On the other hand, I think it laudable if a smoker were to take a N/S room and refrain from smoking while there, in order to cut down on his/her addiction. As I am currently taking addiction related subjects in both Psychiatry and Environmental Health, I have been made aware that N/S or smoke free zones on airplanes, restaurants, etc., do help some to break their addiction. That is why so many tobacco companies are against smoke free environments, because it has a negative effect on their customer base.