Paranoid over-regulation of e-cigarette equipment by people who don't understand it.
Example 1: If you buy say, a spare battery, or a replacement tank, or some filament wire to build a head, you'll find a warning sticker on it telling you that it "contains nicotine". But of course, it does no such thing. You'll also have to provide ID to the Amazon driver as the product "contains nicotine". No it bloody doesn't. Only if I buy liquid, and only if I buy the liquid with nicotine in it, and only when I fill that tank, does the tank then contain nicotine.
It's like selling glass tumblers to over 18's only, because "they contain alcohol". No they don't! Only if you put alcohol in them!
Example 2: Liquid used to be sold in 30ml or 50ml bottles, so I would buy 200ml in 4 bottles. Now, thanks to overthink by regulators, I'm restricted to buying it in containers of no more than 10ml, because clearly the previous 30ml and 50ml bottles could be deadly in a way that 3 or 5 x 10ml bottles cannot.
So I still buy 200ml of liquid, but it now comes in 20 x 10ml bottles which is more expensive and far worse for the environment. But safer, apparently.