With no real health care concerns: If E-cigs look too much like real cigarettes, that is bad. If E-cigs don't look like them, that is really bad.

Jacob Sullum has this at Reason.com:

The main rap against e-cigarettes, as summarized by the Los Angeles Times in its story about that city's brand-new ban on vaping in public, is that they look so much like the real thing that they could "make smoking socially acceptable after years of public opinion campaigns to discourage the habit," thereby "undermining a half-century of successful tobacco control." By contrast, the main rap against e-hookahs, as explained by The New York Times today, is that they are "shrewdly marketed to avoid the stigma associated with cigarettes of any kind." They do not look like hookahs, but neither do they resemble conventional cigarettes, since these vapor-emitting cylinders "come in a rainbow of colors and candy-sweet flavors." In fact, they are so distinctive in appearance and branding that people who buy them do not necessarily identify themselves as e-cigarette users. . . .