Sadiesnan, forgive me for not having read all the posts before commenting (I'm about to dish up our evening meal). I have two dogs, currently 3 as I'm minding a 12 month old dog for my daughter and her partner (they have an 8 day old baby yippee)
I'm splenetic about lazy dog walkers, often in my experience, "professional dog walkers" who don't pick up after their dogs. We did a three mile walk around a local reservoir this morning. We kept all 3 dogs on leads until they'd done the necessary so we knew where they were and could pick up. I was honestly taken aback by the amount of dog pooh at the entrance to the walk, where dogs had obviously been let off,done their stuff and their owners had simply walked on. This walk is well used by families with children in buggies, walking or riding their little cycles. It's gross, disgusting and beyond words to be honest.
Our local park is a joy but is increasingly used by "professional" dog walkers, who in our borough are allowed to walk 6 dogs at a time. They arrive, open their van doors and let the dogs run. Needless to say they don't know where their various charges are toiletting and I have honestly,never yet seen one of them with the necessary black back full of yuck.
I've phoned the dog wardens, our local counsellors, grumbled and gently commented to the professionals, and been given an ear full of abuse by one chap. I despair