Section 156 of the New York State Vehicle and Traffic Law defines a trailer as:
“Any vehicle not propelled by its own power, drawn on the public highways by a motor vehicle as defined in section one hundred twenty-five operated thereon, except motorcycle side cars, vehicles being towed by a non-rigid support and vehicles designed and primarily used for other purposes and only occasionally drawn by such a motor vehicle.”
The "...vehicles being towed by a non-rigid support and vehicles designed and primarily used for other purposes and only occasionally drawn by such a motor vehicle." portion makes it pretty clear that NY at least, does not class a toad as a "trailer".