i'm a dog person (and my dog is a maniac who now has to be muzzled in public) so i tend to be understanding around other people's disruptive dogs, but i believe that as an owner you have to assume that people don't like your dog in their face, on their picnic bench etc. and so you should take steps to prevent it. at least, in the city anyway. in the country dogs can wander around and generally behave as they like and no one seems to mind. it's great.