But the choice is not exactly "either-or", it's between "smog + cigarette smoke" and "only smog". It's like saying that me sitting on your head is nothing compared to the metric ton of pressure already pressing down on you. You still wouldn't want the two stacking up on top of each other.Maybe she wouldn't have to do that if there were no smoking bans created by hypochondriacs exclusively to inconvenience smokers in public places. Because y'know, the odd cigarette someone's smoking across the room is more harmful to you than smog you breathe in 24/7 created by billions of cars, a bunch of factories and some power plants for good measure.
Farting is another thing that's not linked to lung cancer, but you would still complain if I kept doing it across the room.