I don't use tobacco at all, but I believe users have rights, too, & I try to respect them. And smokers should observe etiquette in places where smoking is not regulated. For example, one shouldn't smoke in closed rooms with others present, in elevator cars, or other occupied confined spaces. But I see nothing wrong with smoking in open places, long as the butts are properly disposed of.
Chewing or dipping? Most of the probs from that come from spitting. Again, etiquette should prevail. Don't spit where people hafta walk thru it. Don't set spit cups where they'll easily become tipped over, on a floor, sidewalk, etc. be careful spitting from a moving vehicle when going slow enough to not have it blown back in the spitter's face. Don't spit in places where one wouldn't otherwise spit if not using tobacco.
Once, while riding a MC, a passenger in a car going the opposite direction hookshotted a spit cup into my path, & I barely ducked it. The dude wasn't looking at me at all & I'm sure he had no malice toward me, but he was still a litterbug, of course.
Such misuses & breaches of common etiquette is what brings about restrictive regulations on tobacco use. But I believe non-users should respect users' rights as well.
