Want to ban vaping? Ban goddamned cigarettes too, then, if you want to be anywhere close to consistent.
Regulate the market like cigarettes are, but damn, why outright ban it?
Well that's bad faith if I've ever seen it. Not every industry out there has to be "useful", some are there for convenience. One could also argue that allowing people to switch from vaping to smoking is a huge plus in risk reduction and potentially (for now, with the data we have, more than likely) health.
That's not bad faith, that's arguing over semantics. You two clearly have different definitions of "useful".