Learn some basic science before making idiots of yourselves
The shocking ignorance of the people posting on this comment blows my mind. It wouldn't be so bad if it was the bbc website, but you muppets are supposed to know something about technology and therefore science.
You may have heard about this thing called energy. Fantastic stuff, you can use it to run machines like computers (finally, an IT angle to this otherwise mindless topic), cars or your body. Thermodynamics is the thing which tells you how it all fits together.
Now a decent animal body can convert energy with pretty poor efficiency. I believe a pig needs to consume about 7 times the food (energy) (not sure of that number, know it is > 2) you or I can extract from said pig when we eat it. Vegetarianism is about cutting out the middle man (or pig) and using the raw plant energy more efficiently, where possible. Fair enough to eat a sheep (or even better venison) from some beautiful Welsh or Scottish upland. What else were we going to do with the space? Some fish is even more efficient (just forget about farmed salmon, it's carnivorous). I approach this as a technical problem of efficiency, so flesh sourced from otherwise 'useless' space (from a farming or aquaculture perspective) is fine.
Yes, the population is too large. What in the name of Jobs are you going to do about it? If your answer is to reduce the population from 6 billion to 500 million before we see an ecological BSOD then you are talking about genocide! We or have to consume less farmed meat. Or else stop wasting energy running pointless websites where irate people can vent their frustrations. Oh wait a second... <click>