there is a reason why i vape secretly whenever i am doing errands in the city. I find people to be open to smoking pot but will bite your head off if you're smoking a cig (or appear to be smoking). And with the mayor looking to tax cig butts as well as the ban of selling cigs in drugstores as of last year...let's just say I think one day the words "I'm a smoker" will be received as warmly as the phrase "I'm a pedophile." in SF.
That being said, expect to give some explanations. I, on the other hand, prefer to vape inconspicuously to avoid speaking with self-pretentious hard-headed people (I have tried). But feel free to try your cards, if you wish.
On a lighter note, perhaps you should think of looking at the SF area forum? There's a thread with a few E-cig friendly bars listed. As soon as my classes conclude (2 weeks) I'm spending this summer shamelessly
vaping in areas that my friends and I frequent (public libraries, theatres, restaurants, bars, cafes) to see what places allow
vaping or not. I'll do my best to update when I start.