Drug users were using this type of equipment before ex-smokers were. Not identical equipment, but the same concept. So I'm not sure what purpose bringing them up provides. Seems like you're throwing crap at the wall and hoping some of it sticks.
Plus the fact that those using vaping devices for "illicit substances" are most likely doing it in private, where no one sees them anyway. If they're doing it in public, then they REALLY ARE idiots, and need to be jailed for that, if for no other reason!
I don't think ex-smokers are the only ones who should benefit from vaping -- some folks use 0mg sweet flavors to keep from snacking so much, an entirely useful and viable reason for vaping.
If someone wants to vape because their friends do, then sure, why not? That's why I started smoking. And if it PREVENTS young people from ever taking up smoking, then it has served a valuable purpose. My quandary in this (OP's) situation is, if you don't need to quit smoking because you don't smoke... and you have to lie to your family and hide it... it seems rather pointless, a waste of money, and a bad precedent (the dishonesty) to set for yourself.
But I also agree that 18 yr olds are pretty much going to do it THEIR way, no matter what anyone says, so why bother? Go on and vape, lie to your family; it's not my problem and never will be, but don't say you weren't warned that there might be unpleasant consequences -- for the lying.
If you never consider the consequences of your actions, then you deserve them, whatever they are.
Andria