I think that's the key isn't it.... if you don't know what you're eating and you can't tell the difference between types of meats then it really doesn't matter all that much. My little sister had an aversion to pork when she was a kid, so when we had pork my parents just called it lamb and she was fine. A few times she said 'this lamb tastes different' but they just said it was cooked differently. I think my Dad could've blagged her through a hog roast with enough of a run up.

My parents weren't prize winning when it came to ethics. Pragmatic though.