[Barrin92]

here in Germany distilling your own spirits is illegal (I think there's an exception for very small personal amounts), and yet I don't think I've ever seen some sort of early 20th century moonshine market.

I've seen these arguments about enforcement frequently but we're talking about modern governments here. If Uncle Sam wants to stop flavoured smoking they will be successful. They can go after online platforms that don't shut these exchanges down, they can go after individual sellers with harsh punishments, and so on.

I very much doubt the margins on vaping products are so high that someone is going to risk their neck over it. Menthol cigarettes in the EU were banned a few years ago and I can't remember having seen one in a long time.

[giobox]

My understanding is while some EU States have taken it upon themselves to implement a ban sooner, the EU directive banning them doesn't come into effect till 2020. You can still happily buy Menthol cigarettes in the UK, for example.

[cwkoss]

Check out "Air stills". Distilling your own alcohol is illegal (in US), but it's now about as easy as operating a coffee maker.