I have always thought that smoking would be far less of an issue if smokers were as strategic as non-smokers.
A non-smoker will glance around a bar or restaurant that allows smoking and find the place to sit where it will be the least offensive (ie. as far as possible from the smoke — not far from the smokers, as far as possible from the smoke.)
I honestly don’t often see smokers giving their seating the same kind of thought. (Sometimes the smokers don’t want to be near other people’s smoke either.)
I’ve seen smokers, not only sit near the non-smokers, sit down with their friends, and to be polite to thier (smoking, or non-smoking companions) when they light up, hold their smoldering cigarette behind them (as far away as possible from their companions) and, quite likely in a spot to invade their neighbor with smoke.
An aside: Why do so many restaurants make it necessary to walk through the smoking section to get to the non-smoking section. Another aside: If a table is on the edge of the non-smoking section and adjacent to a smoker’s table, it is not nice to put a non-smoker in that seat. (Steak and Shake used to be guilty of both infractions.)