My wife used to smoke. She quit a couple of years ago with the help of e-cigs, which she still uses. I hate smoking and the smell (yes, I'm a reformed smoker and you know how we can get). She agreed not to smoke in the house but even when she went out to the garage I could still smell it. Now she can smoke an e-cig in the car next to me and I hardly notice.

Not sure why people would find them any more unacceptable than drinking beer on the plane (which has a stronger odor than an e-cig). Or having a smoking room in the boarding area and then having someone with smoked drenched clothes sit next to you.