I've only been there once in my life, so no specific suggestions. If you stay at a family run type hotel one night, there's always the possibility of being able to leave the car in an out of the way place if the folks are friendly and have room.
In small towns, one could also make friendly enquiries at a local OPP station, Ontario Provincial Police.
All these depend on luck and how you approach people, but if they know you are spending time and money in their communities, chances are most likely good.
good luck