There is some appallingly ill-informed maths in this thread.
Peanuts and cows equated to deaths per meal is particularly cute and special.
What did the cow eat to get so big?
Cows need energy to move around and do everything, and they get it from plants like grass or hay, which is the reason why it's not 100% efficient. The exact rate varies depending upon the animal; insects seem to waste less energy from what they eat than cows.
This entire argument (about how plants are on the same tier as animals) seems like a devil's advocacy, except it doesn't sound like they believe otherwise. Ideally we'd all photosynthesize and eat the waste of other animals (worms, for example, get their nutrients and energy from dirt), but all of the humans I know aren't evolutionarily equipped for that., and also wouldn't enjoy eating those things if they could. Regardless of how "moral" anything is, doing that just isn't practical unless you're a plant or a worm.
I've now realized that it's not the ability to feel, and react (which is probably just something that all living things possess) that makes a life sacred. My iPhone can feel a touch, hear sounds, or "see" things and react, but it's not sacred. The reason why animals are a sacred form of life (this statement is unrelated to religion; I'm using it to describe the things that have a life worth living...) is because they have personalities. I think the emphasis (at least in American culture) on the different personalities of cats and dogs is why it's so painful to imagine the Chinese eating them. It doesn't matter how they got their personality, but it's a fact that the personalities of litter-mates (AKA being twins or a higher order multiple) are often very different. I have never seen any evidence to suggest that plants have personalities in the few ways that they react to stimuli. You can only pretend that they have personalities.
I'm not going to argue about material wastefulness, because I think that it's, in general, bad; however, it's possible to have either type of diet and be wasteful or otherwise. This is true for resources like water, as well.
I also think that my comments on capitalism, though unexpected, were not unwarranted. The only reason that these "evil meat companies" still exist is because they have an income from their "evil meat products". Unless I'm completely wrong, vegetarianism (etc.) is a form of boycott or protest. (I'm not sure if you're also upset with the fact that I only make references to America, where I live and know the culture, but this is because I don't like to assume that other countries are the same as mine. I expect people to realize their country fits the description, because usually the situation's not applicable when it doesn't.)