Livestock production was a way to turn inedible grasses into an edible product. Eating meat is a by-product of living in areas where animals were better prepared to survive in the climate then the nomadic people who lived there. Freezing plains in Mongolia, often poisonous jungles in South America, arid deserts in the Middle East, and the barren mountains in Europe and Asia all maintained large, ancient groups of humans where the environment would have killed them, whereas the native wildlife was accustomed to the vegetation or the environment itself. Without going into too much evolutionary biology, Humans are able to eat and process meat, and at that time it was needed. In our current globalized market we have access to all food, all year. People don't need to eat meat. It is a choice for the percentage of humanity that can afford to do so. The modern system of centralized livestock rearing is the cheapest method of raising that product available, and even though it appears to be cold and distant to people who have little experience in the process, the techniques used in raising animals in a modern system have been developed taking into account all of the necessities that the particular animal needs. It is not traditional, it is not romantic, it is not natural, but as a self aware organism, humanity refuses to stay traditional, romantic or natural; we always grow and move forward.