You’re of course totally right. And yes people can’t eat just grass or veggies. What this is pointing at is the need to not each as much “factory farmed, cage ridden meat” and eat more grass fed beef. Eat less of a bad thing and eat more of a good thing.

The local bison and elk that I eat have not been fed grains, corn, or any other commercial feed. They eat only grass from the pasture and are not confined, not fed antibiotics, or any other wastes such as chicken manure and feathers. People can’t eat grass! These animals convert grass into food for us. The manure goes back into the pasture naturally and keeps the soil healthy. I may be wrong but without force feeding grains/corn, I also don’t think the animals fart excessive methane.

Ethical meat eaters also eat plants, both fruit and vegetables. Humans are omnivorous and a strictly vege diet is unnatural and potentially unhealthy. Let’s balance our food intake and stop demonizing meat eaters.

World wide the amount of carbon – organic matter has declined significantly with modern farming methods. This has caused a significant amount of carbon emissions as well as a decrease in the fertility of our soils lessening yields per acre and decreasing ability of the soil to produce healthy food. With intensively managed livestock we could heal much of the soils increasing crop yields, nutrient content of food and sequester carbon rapidly into a semi-stable (so long as the land is sustainably farmed) carbon sink. So for sure, industrial farming of livestock produces tonnes of carbon but that doesn’t mean that all livestock production methods are net carbon emitters. Eating intensively raised grass fed sheep, beef and goat in minimal amounts could be doing the Earth a big favour! Awesome link for further reading:
http://www.holisticmanagement.org/n9/about/carbon.php