Some might argue that while eating meat is in general acceptable, we are under an obligation to abstain from meat produced in particularly harsh ways: from veal perhaps, or from lobster or from pâté de foie gras. Others might argue that what is important is the level of the animal's evolutionary development, so that while it is acceptable to eat poultry one should abstain from the flesh of animals, or while it is acceptable to eat fish one should abstain from the flesh of warm-blooded animals. Or one might distinguish according to the kinds of value which may justify the eating of meat: turkey dinners on holidays with the family might be thought legitimate, while a bachelor cooking for himself would be under an obligation to abstain from meat. And there are many who see nothing wrong with buying meat at a supermarket, while disapproving of hunting even when the resulting meat is eaten by the hunter's family. Finally, one might, without accepting vegetarian ideas oneself, still feel that vegetarians are entitled to the kind of respect frequently accorded to pacifists by those who do not share their convictions.
(Philip E. Devine, "The Moral Basis of Vegetarianism," Philosophy 53 [October 1978]: 481-505, at 502 [footnote omitted])