 So the dog just assumes that what he did was exactly what he should be doing. It's the same reason dogs chase cars. The dog always wins. The mailman comes, he makes noise, the dog barks, the mailman goes away, the dog always wins. In certain situations, the best thing for the mailman to do is to take the opportunity to get, and you're right, it's the owners, not the dogs, but to get to know the dogs in the neighborhood. That's the ideal situation.