I see plenty reason for them to ban it. Consider someone going only 9 MPH among a crowd in Manhattan and there's an old lady who just randomly decides to divert her course of walk...
Anyway, not sure if the ban is on streets, on sidewalks or both. From what @KOLHAOLAM mentioned it says ...used on ST.
+1
Too dangerous for the sidewalk, too dangerous for the road.
That's BS. You guys are parroting these old fogey politicians who shouldn't be making these ridiculous laws.
A hoverboard is not more dangerous than a bicycle.
And of course, anyone going 9mph through a thick Manhattan crowd will have to get their brain checked. But it's never going to happen, for the same reason you don't see bikers going through crowds at 9mph.
Just the same old "scared of new-fangled technology" mentality if I've ever seen it.