@sjw May be surprised how often people take in a stray puppy to find out it's a coyote. Pic related came in to a vet office for a visit, no idea their dog was a coyote.
Fun fact: the US does not recognize rabies vaccines being effective in coyotes or wolves. I recommend rabies vaccine anyway, but this means that if the dog bites someone even if UTD on rabies, it may have to be quarantined or tested.