That’s an interesting title, because not too long ago there was no other kind.
It now seems common for members of our Saran-wrapped society to grow as appalled by the site of a cat on grass as they do seeing an unaccompanied child walking on a sidewalk. This article covers the ethical strengths and flaws of arguments on all three sides of the issue. No one is comfortable.
Then again, where is it written that any of us should be?