I'm a professional dog walker in the Beaches/Scarborough areas, and all I can tell you is to keep bugging the councillors and Toronto Animal Services. I have had to give up dog walking in the Scarborough Bluffs areas because dog walkers go there with a bunch of dogs and let them run wild. I've called TAS several times but the same dog walkers continue to go there. In fact, one time when I complained, I found a notice in my mailbox saying that someone complained that I had 4 offleash dogs in the park, when in fact I was the one who complained!
I think that if enough of you complain frequently, that's the only way they'll do something. They are very understaffed, but the plan is they are going to hire another 10 or so officers and give them the power to arrest. Dog walkers in the past have refused to give their identification and unless a police officer was also there, the TAS officer couldn't arrest or fine them.
Incidentally, all dog walkers with 4-6 dogs must wear their permit visibly, so if you see someone with that number of dogs, they should have the permit and if the dogs are offleash, you can write down the number, take a picture if you have a camera handy, and submit that to the authorities. Not that a digital picture usually stands up as evidence, but at least that might help your case.
I've just cut way down on the dog walks and focus on backyard dog visits and pet sitting. There are just too many bad dog walkers out there and they give all of us a bad name.