Licencing seems like a good first step (that, I find it mindboggling didn't already exist).
It's not like the same level of enforcement is needed continuously.
I kinda do think shutting down and charging shop owners would be enough to massively curb the trade. It wouldn't stop it, but suddenly it becomes more of a pain to buy.
Currently shops are doing this in the open. How hard would it be, honestly, to make a tip line (internet form), have a small team of inspectors go around, charge and shut people down? It kinda feels like this isn't even being done.
And if funding is the problem, well, it kinda pays for itself.
Gotta make it juuuust enough of a pain that you either quit, or are willing to pay the extortionate excise.
Can't really argue with the results, we massively curbed smoking in this country until vapes showed up.
Yeah, we've dropped the ball. You actually need to do some enforcement to make this work, seems like that's hardly being done. And increases in enforcement would pay for itself.
Making something annoying to do definitely is a winning strategy.
It's not even criminal to use a VPN in China, but they are banned and make it very difficult use, you just accept your fate that they don't really work anymore. It's still possible to circumvent the Great Firewall, but requires way more effort than before. Most people just don't, even those with a desire to.
Just that for our purposes, it's for something worthwhile (In my opinion. Smoking is dumb, and as stated in another comment, someone's "freedom" to do it isn't convincing if you want to live in a social democracy.)