I'm not saying that I'm in favor of the mindless killing. Far from it.

But if there wasn't a demand for meat any more, the mass amounts of cows, pigs, and whatever animal used for meat will be declining drastically. Because of the greed ppl have, and the lack of income generated by the holding of cows, ppl will abandon these activities.
As far as the rhino, or the minx's coat. It's cheaper to do it illegal.
Again..I'm not favoring that industry, but if one would hold rhinos and just saw off their horns (without killing them) the population would increase. Same goes for the minx population, despite the fact that they will have to be slaughtered to get their fur. But what if those animals were given a rich life (as far as possible in captivity) and when they die of old age..their fur can be gained..

And yes, greed does make blind.

Oh, heard about that cloning company that wants to return the tasmanian tiger? Not sure what I should think of that yet.