The villain is just trying to prove his authenticity (at the expense of harming an endangered species -- so unacceptable) and has surrounded himself with talking dogs in that effort (it's a cartoon, and Disney knows how to animate dogs).
I saw this as a double feature with Groundhog Day (later, back at my place) so that may color my thinking (deja vu is a theme).
The "little mail man" (pun) looks like Humpty Dumpty and brightens the picture right from the start, turning a potentially bitter old man story into an heroic epic instead. Uplifting.
