While I think both of those points are very debatable (just search YouTube for factory farming videos if you really think livestock conditions are better), they still miss the point. After all, both of your points could just as easily apply to dogs, cats, horses, whales, chimpanzees and heck, even humans. My main argument is that there is really no morally consistent way to think that eating dogs, cats, horses or whales is abhorrent but eating pigs or cows is OK.

I think you are correct, but agreeing with you on the lack of moral consistency does not drive me to cut meat out of my diet. I've never tried dog, but I certainly would. I keep dogs as pets and I would never eat my own dogs. They have emotional value to me, by my own design, as that's the purpose I've given them in my life.

There are many reasons to why we wouldn't eat certain animals. Cats hunt rodents, dogs are protective, horses provide transportation. Cows don't do any of those things well, and they also taste wonderful.

It’s strictly cultural. Every grocery store in Switzerland sells horse cold-cuts.

See my response here[0] on whether living in nature or on a factory farm is more more horrific. The gist is: each breeding pair of animals produces, on average, just two offspring who themselves live to reproduce. The implication is that the vast majority of animals ever born die of predation, starvation, or via exposure to the elements. Nature is a bloodbath.

[0]: https://news.ycombinator.com/item?id=18773106

We don't give equal moral weight to all humans, so why would we give equal moral weight to all animals?

There are a lot of documentaries (Earthlings, Dominion) or books (Eating Animals, Fast Food Nation) on animal agriculture that would give you a better counterpoint to #1 than I will in this comment. Or just Google image search "factory farm", "battery cage", "gestation crate".

If #2 justified animal agriculture it could also be used to justify human slavery, provided you intentionally bred humans for that purpose.

Regarding factory farming vs. life in a state of nature: on average, each breeding pair of animals will produce just two offspring that live to maturity and reproduce. Which means that the vast majority of animals ever born will die of something other than old age. And mostly those deaths will come via predation, starvation, or by freezing to death (in northern climates). In other words, the scale of death and misery in nature is massive.

And regarding my second point somehow justifying human slavery: that's only true if your moral system somehow makes humans and animals out to be equivalent. But we don't even make different classes of humans morally equivalent to each other, so why would we make animals morally equivalent to humans?

A life of pain and suffering on a factory farm is worse than a natural life, where there is at least the possibility of joy and natural behavior. The only thing many factory-farmed animals ever touch is steel, concrete, and their own waste; they never see the sun nor feel the wind. Many are artificially inseminated, so they don't reproduce naturally. Many never see live plants, let alone eat them, so they don't feed naturally. Many live in cages so small they can't turn around or stand up, others so packed together that they go crazy and resort to cannibalism. To mitigate or prevent cannibalism, pigs and chickens are mutilated in various ways. From lack of exercise and intense weight gain many can't stand on their own for the later portions of their short lives. The scale and degree of cruelty that factory farming inflicts on animals is really incredible, and I think it says something horrible about humanity.