Kids vaping is often a mental health problem, not a criminal problem. Nicotine is used by people with untreated mental illness to self medicate, and as long as you have kids without adequate access to mental health care you’re going to have kids vaping. From what I can find something like 1/3rd of people who need mental health services in Canada haven’t got the care they needed in the past year. That’s a lot of kids.
Criminalizing selling but not possession is a very basic way of preventing the criminalization of addiction. Throwing a kid with untreated or badly controlled ADHD into juvie, or fining them, or whatever punishment you’re imagining here, is basically the worst way to deal with addiction.
Because I’m sure someone will misconstrue this as me saying it’s okay for kids to vape: it’s not, that’s why they need mental health services, even if it’s ‘only’ for addiction. Criminalizing them doesn’t help them.