Wow, I wonder who presented that for a by-law and how much research went into it. I think it's a silly one that cannot be monitored and if there is a complaint someone used one it will be he said, she said.
Good thing I never have reason to walk Oban in TO. Oban always wears his Volhard collar if only because when I let him off leash I take the collar too and the way it does up allows me to easily fasten it around my waist.