In BC Canada, all OHV, including snowmobiles require registration too operate just about everywhere. They say you don't require liability insurance but you cannot use any of the FSR if you don't have it, so this also mean you cannot off load your OHV from a trailer or truck if it is off loaded on a public FSR (crown land roads). The fines are very stiff, even impound of vehicles.
In our high alpine areas, much is only accessible by snowmobiles from a certain date to a certain date and no other form of motorized wheel vehicle at any time of year may access. I believed wheeled vehicles, including motorcycles have an elevation limit and beyond is off limit. These off limits do not apply to snowmobiles because of the limited environmental impact they have in comparison.
Finally we do have to buy trail passes to operate a snowmobile on designated trail system that take you into play zones in the mountains, these trail systems are leased and operated by clubs that are responsible to the grooming and maintenance of trails and cabins found in the system. There are numerous clubs and trail systems found through out the province and only snowmobiles have access.