If you live there, use a bandana over the prong collar. Chances of actually being fined are slim. The alternatives suggested are halti's, which are far more adversive and dangerous for most dogs.
My previous gsd suffered whiplash on a halti.
I've never had a dog injured or even upset with wearing a prong. All of them hated the halti (I have no clue why I keep experimenting).
Of course, you could try without, and just ALWAYS set your dog up for success. Never reward your dog for pulling (ie, stop walking the moment your dog pulls, don't resume until the dog gives you slack), never take your dog anywhere that the dog might be rewarded for pulling or lunging (so, don't go anywhere with squirrels, other dogs, cars, geese, that sort of thing) until your dog is 'ready' for that level of distraction...yeah, right.
Better yet, send an old fashioned snail mail letter objection to the City of Toronto Council requesting a change.
I'm lousy with words, still trying to think of what to do say.
In this article (toronto star)
, apparently, you shouldn't have a dog if you need a prong collar to control your dog. Wow. My 40 lb dog on a harness (why do I always get sucked in to trying the all positive way) permanently damaged the tendons in my left hand. He's a nice dog, but he did a fast dart towards the street and I panicked and grabbed the leash wrong...he hates halti's btw.
theres a change.org petition too, but I think individual letters would be better.