One of the few places I feel totally comfortable vaping is a pharmacy of all places. I'm a regular customer and the pharmacy staff knows me by name. I was just there and vaped all through the store. No comments, no funny looks. I do use my cig-alike when I vape there because as much as I like my vape box, I feel people will think I'm using something illegal, like a portable .....
It just seems easier, if asked, to explain the e-cig if it looks like an analogue. It's obviously not a cigarette but is in a form people are used to seeing. I use my cig-alike in the grocery store as well. I have gotten curious looks there, but no one says anything, which kind of surprises me.