In response to my questions my favorite commentator defends the keeping of pets and the riding of horses with the idea that dogs/horses and humans share a symbiotic relationship. It is certainly the case that some humans need their dogs and enjoy their horses, while the same dogs and horses need, or at least seem to have better lives when in, the care of these humans. Still, I have some problems with this. Humans may have brought about this state of affairs, in which case the moral question may be how to undo the symbiosis rather than to perpetuate it. To take an extreme example, a slave may be dependent on his master, but our reaction is to emancipate the slave even knowing that there will be a transition period that might be painful for ex-slaves.
Moreover, when vegans avoid exploiting animals animals they too make some animals, born and unborn, worse off. Chickens in a commercial coop are also dependent on humans. Of course, most of these chickens would never have been born if not for non-vegan humans.
I do not "own" a dog, and that might make me a better -- or much worse -- observer of human-dog relations. I have some trouble watching dogs on leashes. I understand that this can be defended as advancing the safety of the dog, which might otherwise run into the street or conflict with another dog or human. I would have thought that people who do not wear leather would also not pull dogs by their necks.
I hope my readers know that I do not mean these comments in a judgmental way. First, I hardly expect people and especially myself to be consistent. I admire people who try to do good and to live cooperatively on our planet; if they do 5/7 of the non-exploitative things, that is pretty good and more than I usually do (especially when I was more the curious carnivore than the curious vegan). Second, I am simply the curious temporary vegan. I am trying to understand why keeping pets is not abhorrent to people who do not eat meat or even animal products.