I vape in restaurants where smoking isn't allowed. And when shopping at Walmart, Home Depot, etc. I try to be reasonably subtle about it, but I'm certainly doing it in public. I go dancing once or twice a week, and I vape there, but that's in a smoking bar. I haven't been to a non-smoking bar since I started vaping. That's not intentional, just works out that way.
So far, nobody has ever tried to stop me from doing it, and nobody has given me a hard time about it in any way. A fair number of people have asked me "what is that". Mostly smokers, and most of them are already familiar with an mini e-cig kind of thing. I just tell them it's a bigger, better version of an e-cig. If they show interest, I show them how it works and give them a business card for Vaporescence, a local brick and mortar where I bought my eGo.
I'm thinking of getting some business cards made up that have ECF info on one side, and Vaporescence info on the other.