If it appeals to kids, it's being marketed to kids
... is the extent of the logic behind this claim. There is, in reality, nothing more to it.
As I ponder the 'appeals to kids' suggestion, I wonder if there is any product that appeals to a segment of the adult population but does not appeal to young adults (aka kids). I cannot think of one.
If truly being marketed to kids, then advertisements would be shown with kids using it, enjoying it, and suggesting to
buy (more of) it. We can find those ads with products clearly aimed at kids. We cannot find that with products that are clearly aimed toward adults. Yet, if it still appeals to kids, despite it not blatantly being marketed to them, then one can spin things in a way, let's call that deception, that says it is being marketed to kids.
IMO, the only plausible leg that those who claim it is being marketed to kids is the flavors, and this same person claiming this would have to lie and/or deny their own appeal to flavors like 'cherry soda' and/or 'chocolate mint' not to mention a million other sweet or interesting flavor combinations. That adults may enjoy these same flavors seemingly doesn't enter the minds of those who make the claim of 'who's going to like an ecig flavor that has chocolate in it?'
I fully believe that non-vapers, with a little intelligence, realize that adults are the ones who very much enjoy those flavors, and will get whatever points we vapers would bring up on this tangent. Yet, I can see why these same intelligent non-vapers might scratch their head when flavors like bubblegum are on the menu. Then again, they might not question it, as they may be an adult who very much enjoys bubblegum.
I do think a plausible way around all this is to have flavors being named along lines of, 'adult grape,' or 'adult bubblegum' etc. which would indicate even further who is this being marketed to. At same time, I'm willing to bet the US national debt, that regardless of how those flavors are named, they will still hold appeal to some young adults (aka kids).