I'm from the UK first thing we learn growing up is pick your battles this is not a battle you want to get into you stand to lose a lot and only gain vape convenience. With every parent child dynamic there is that line In the sand that a parent won't back down from they usually make no sense have little connection with logic and cannot be overcome. Let them have this one and walk your backside where ever you have to for you to vape and them to be happy. I get the feeling in this instance you trying to educate them or "prove your point" will be akin to striking a match in a puddle of gas. I also think you hoped you'd find an answer coming to a
vaping forum you got many and it's upto you if you listen to any of them and we can say what we want it won't be us who have to deal with any consequences of our advice and certainly won't be paying to support you if it all goes wrong. Play safe do as they ask finish your education get a decent job and buy/rent your own house then you make the rules.