I actually finally got this argument from someone the other day. Started using over population of deer as an example. I was at a loss other than to say, "Well Factory Farming grossly overproduces cattle to satisfy high demand. If the demand wasn't there, they wouldn't produce as much." He says, "Well, deer over produce and if we didn't hunt they would over-populate. If people didn't eat meat, we would have a couple of cows grazing in this front yard." I just kind of grimaced and said, "I disagree." I'm sure there was a more articulate way of putting my point across. Opinions?