[comex]

> Traditionally, we like to think of animals as serving humans, but in a case like this, isn't the opposite true?

As someone who's lived in a household with dogs and a cat, I never saw it that way. After all, most pets do not provide any practical service to their owners. When I threw a stick over and over to have the puppy bring it back to me, I may have been the one running the show, supposedly the master, but I always thought of it as my service to her; sure, it was enjoyable to me to have something to do outside, and to watch her speed and grace, but humans get tired of repetition a lot faster than dogs (and teaching her to do more interesting things than catch would have been quite a lot of work). Inside the house, it might have been nice seeing the older dog around, and to initiate play when I felt like it, but on the many, many occasions she decided to plop a filthy chew toy next to me on the couch (in the hope that I'd throw it - any attempt to remove the toy from the couch counted as a throw, resulting in her fetching it back to the couch!), I'd hardly associate the resulting exasperation with the feeling of having a servant. And I didn't have many actual duties myself - I'm sure this was felt double by the ones who dealt with their food and daily exercise.

But there's no need to be verbose. A pet is simply a lite version of a human child. Physically, the parent does everything for the child; the reward is emotional, and quite high to make up for the former...

[VLM]

>but humans get tired of repetition a lot faster than dogs

Adult humans, specifically. Thus the natural pairing of kids and dogs. Note this goes both ways, if the kids are driving the parents crazy, "go play fetch with the hound".