In response to the question of where the line can or should be drawn for the eating of meat, there is a fairly simple riposte. If you happen to be an animal that has a colon able to handle the quick digestion and elimination of meat, you should eat meat. Human animals do not have a colon with such ability. The human animal's colon is too long and this results in the rotting of the meat in the colon before it can be eliminated.
In light of the environmental catastrophe which is confronting all animals and, indeed, all life (excluding cockroaches), perhaps it is time that the human animal swallow its pride and declare that we are not able to care for other animals and should eliminate our "need" for pets altogether. The euthanization of over 25 million dogs and cats a year in North America would seem to be a strong enough message that humans are incapable of accepting full responsibility for the earth and its inhabitants. And, this is primarily true of "animal-lovers".