Dogs need space, same as we do, Imagine if a total stranger were to come running up to you shouting “Hi its ok, I am friendly” then proceeded to try and hug you, invading your personal space, how would it make you feel?, would you feel threatened, frightened, scared or uncomfortable? What would you do? Try to move away, tell that person to back-off and if they didn’t, maybe lash out. You would consider that person to have no manners or respect. In other words unacceptable behaviour.
Dogs are no different, they need their our own space too. Yet many dogs have to put up with that kind of behaviour from other dogs, on a daily basis, who’s owners think its ok, to let their dog barge right on up, while shouting “Its ok my dog is friendly” without asking, if its ok to do so.
Its all about manners and respect, we as humans expect to be shown some manners and respect and dogs are no different.