You dont have to be of age to operate one, you have to be of age to OWN one. What does that mean legally? Just like a real gun, you can only loan it out under direct supervision.
So the user of the moment can be of any age, but you, the owner, must be present.
If not, you, the owner, is breaking the law.
Many dont care, or dont know better. If the authorities ever check, the parent is in deep crap.
That's how it works.