I still think it is suspect. Remember, just because it is on the Internet somewhere, doesn't mean it's true. I've seen the "Los Angeles shelter" sentence and numbers many places with no attribution or follow-up.

And yes, rendering plants do exist. They perform a valuable service in our meat-eating society, so that the "leftover" parts of butchered animals do not go to waste or take up room in landfills. It's not a pretty part of life, but without it, life would be much worse. Much like sewage treatment plants - much better than polluting every river and stream with human waste, and killing off wildlife, never mind the cost in terms of disease and air quality for the humans.