There is a book that goes into the ambiguous ethics of pet ownership written by a Bioethicist (who owns some pets)

https://www.amazon.com/Run-Spot-Ethics-Keeping-Pets-ebook/dp...

From a review "no matter how well loved they are, our pets are essentially being held captives…. She reminds us that the animals we love and treat as companions ‘are denied nearly all of their natural behaviors, not to mention their freedom"