Personally i always ask when Im with people if they mind. and when im in public, outside is fair game if you ask me.

Although once i was at a small cafe and one of my best friends is a SERIOUS asthmatic, and there was a guy puffing away at some huge cigar (like he was fiend), and he continuously blew the smoke in my friends direction. so finally i went over (because my friend is far to polite) and asked the gentlemen to please just blow the smoke in a different direction, and i told him why, and i would like to just say the guy was real cool about it and put it out, when all i asked was to blow the smoke in a different direction).

Especially here in the US i get alot of crap from cigar stores, they constantly ask me for an ID, which i gladly give them, and than i get remarks about how young i am, and than once the guy called out my age to everyone who is sitting enjoying their cigars, to make fun, and i laughed with them and than politely told them all to (four lettered word beginning with f ending with uck) off, and told the guy i would no longer shop there (and none of my friends do either now), i am not a big fan of snobbery.