To the best of my knowledge the no-smoking ban (at least in Philadelphia) is a result of constant exposure to 2nd hand tobacco smoke being harmful to employees mostly and customers to a lesser extent. But over time people (particularly non-smokers) seem to have twisted the original intent of the law to mean "you can't do that here just because it annoys me". Well, try saying that to the woman in the next booth who has on enough cheap perfume to make your mashed potatoes taste like a French .....

Funny how things work eh.
Went to an Outback Steakhouse about a month ago. When I asked the bartender I was surprised their policy was to allow vaping. Went to different Outback last week and the hostess said it wasn't allowed in spite of me telling her it was allowed at the other Outback. So I asked my server to ask the manager and NOT the hostess and she came back and said vaping was in fact allowed. I gave my server a nice tip, and on the way out gave the hostess a scolding for acting like a know-it-all and being too lazy to extend me the courtesy of asking the manager herself.
I'm afraid it's gonna be a long time before the right people in the right places see the law for what it is. As it stands now, and IMO, the general public can't tell the difference between smoke & vapor because it looks the same. Getting past that seems to burn too many brain cells for many people. I think the only way it will really sink in is when they complain about the vaper sitting next to them and are told by management that there's nothing harmful about it, it's not against the law, and that they can leave if they don't like it.