It's not known to a lot of people but even diseased animals will be thrown into slaughter for consumption. Last year there was America's biggest beef (at one factory farm) recall due to sick animals being sold but who knows how many other companies are doing this as well.

We consume 15 billion animals a year (statistics as of 2007, our consumption has probably raised since). If there were no factory farms and mass production all animals would not exist because of us. We do not need to eat meat everyday.