In the defence of dog-friendly dogs, my dog will approach any dog, but if that dog is not friendly and perhaps wants to attack her, she veers away before coming in range and walks away. I don't call her off if she's approaching a dog that doesn't like her because she'll satisfy her own curiosity

it's not an issue of friendly or not- my dogs are all friendly- I don't want YOUR DOG coming up to MY DOGS. Ever. Anywhere. If I wanted to arrange a play-date I would. On leash, off leash, it's beyond rude to allow your dog to just walk up to another dog without asking the owner for permission first.