First of all, it's untrue that you can shoot an antique anywhere you can shoot a non-restricted firearm. It depends on the province you are in. Nova Scotia, for example, will not permit the discharge of antique revolvers in a wildlife habitat (which accordingly has been deemed anywhere outside of your home). These can only be legally discharged at a range. They are first and foremost considered to be handguns, even if not legally 'firearms' under the Firearms Act. This was explained to me by a provincial Department of Natural Resources Officer.
For the same reasoning, I predict antique firearms will eventually fall under the 'freeze'...that although they aren't firearms under the Act, they remain handguns, and therefore are subject to the ban. Once Poly realizes this they'll start harassing the government about it and that will be the end of it.
The saving grace is that none of these handguns are registered, aside from those having had antique status certifications prepared by the RCMP. Even then, they are tradeable, so one only needs to assert they have long since been sold or passed on to another individual.