In the hopes of steering somewhat away from the relative merits of meat-free diets, I wonder if anyone has considered the real-world implications to ending widespread meat consumption in the western world? I'd think that if there were no more demand for meat, a lot of farms would suddenly go out of business. True, there are eggs, meat and wool, but if every animal too old or the wrong gender to produce those ceased being an asset and became a liability in one stroke? Suddenly thousands of farms have the choice between going out of business or destroying those animals. Since we're assuming for the purposes of the discussion that the latter is abhorrent (if the law gives them a choice), what happens to the animals then? I doubt charities and suchlike will be able to deal with more than a small fraction. If there was enough money you could ship them off to third-world countries, but let's face it, there they would be eaten or what's the point? And failing all that, just being left to wander? Domesticated animals could not live that way. Some might eke out an existence but vast numbers would die from predators, disease, exposure and general inability to support themselves.
Frankly, in most cases, a farm is the better option for the animals. Unless you (the non-specific, world-in-general "you") possess the ability to photosynthesise or are a special kind of bacteria found near volcanic vents deep beneath the oceans, it's a fact of life that your survival depends on consuming other living things. I hate to throw around the word 'natural' in a debate because it's so subjective and usually means "the way I think things should be", but in this case I think it's justified to say that death, particularly dying to feed another, is a natural part of life and not, in and of itself, a bad thing. Circle of Life, and all that. So I can't find anything wrong with providing animals with food, shelter and care over the course of their lives, then a quick and humane end, in exchange for what we need.
It would be a much better argument if so many animals weren't reared in appalling conditions, unfortunately. Battery farms are horrible places, for example. I think here in the UK we're gradually becoming aware of that, and I can only hope the trend spreads.