You specically said If they’re just nicotine, I don’t really see the problem. All the problems that come from smoking, aren’t caused by the nicotine, but by the delivery vehicle, and in this case, doesn’t seem to be an issue.. Emphasis mine. You seem to be suggesting that there is no risk associated with these kids using nicotine products? The link I provided indicates the opposite:

Animal research has found that even in small doses, nicotine exposure in adolescence causes long-lasting changes in brain development, which could have negative implications in human adolescents for learning, memory, attention, behavior problems, and future addiction.