I am sick and tired of going to the park and having some carefree dog owner with the dog off the leash let their blasted mutt scare the hell out of my DD (and ME!). "He's only being friendly" is not an excuse for allowing your dog to run at a child.
And then when we get to somewhere nice to have a picnic, I have to scour the area for dog turds before we can sit down.
I think it's time we acknowledged that although many (maybe even most) dog owners are responsible, the only realistic thing to do is to exclude dogs from large parts of public parks. No apologies to sensible owners of dogs - it's a collective responsibility for all of us (non-dog owners included).