Into this latter scenario, the instructor once brought her dog. The next day, we were once again a dogless classroom, but something had changed. Suddenly people had feelings to share. People spoke in resentment at how they had sat in class for weeks with barely a nod from anyone, but that a dog who spent only moments was greeted warmly and in a welcoming spirit. From the stories above an answer, my answer, begins to emerge.
Dogs are useful, certainly.
The guide the blind, serve the disabled, pull sleds, hunt game, protect households and perform police, tracking and rescue tasks. There is no doubt that dogs are functionally useful in these and other ways. I do not, however, believe that this is the answer to why people own dogs. A dog, in our presence is a well of welcome, of comfort and of love from which we may draw. I see it every day.