> Other than in terms of human opinion

That's the point though. We don't eat horse either in many areas, for the same reason. Ever heard the phrase, "cattle, not pets" when referring to managing systems? As humans, we tend to form bonds with specific individual dogs, cats, horses, etc. But cattle, not really. That's not to say the animal doesn't have the ability, but they don't easily fit into our lifestyle. (I can let a dog loose in my house while I go to work - a cow, not so much.)