During the 1970s parents were purchasing minibikes for kids, either the cheap "frame bikes" with Briggs & Stratton engines or the fancier Honda 50 (and some, like me, mounted lawnmower engines to old pedal bikes with varying degress of success or safety

). The difference was, we all knew they weren't legal for road use, and they didn't look like anything that
was street legal, so there was no confusion. City kids didn't have them, but there were a few in every suburban neighborhood.
When the first mopeds came out during the 1970s gas crisis, the rule (at least in NY state) was you had to have a drivers license (not necessarily a motorcycle license) to ride it on the roads.