How do religious people justify raising and slaughtering animals for food?

[Angrboda]

Your confidence in your opinion of the morals of the matter is decidedly misplaced.  You're welcome to have an opinion, but representing it as an objective fact is stupid.  I'm a meat eater and proud of it.  In my opinion, morals, the human science of right and wrong, only applies to actions which affect other humans.  To suggest that there is something immoral by causing suffering in non-human animals  is in my opinion a mistaken understanding of morality.  It might be argued that there is some moral significance to eliminating gratuitous suffering of food animals, but that, if so, would be a secondary matter.  As far as I can see, the only practical implication it has is in helping us preserve an image of ourselves which is invested in being an animal samaritan, and possible ecological repercussions.  Beyond that, fuck 'em; they're food.

To clarify, you don't think torturing/abusing animals is immoral?

It's not in and of itself immoral, no, but it does have consequences for our behavior toward other humans which can't be ignored. A species which encourages cruelty toward other species ends up promoting that behavior towards its own. Depending upon what one considers the basis of morals, that may or may not make it a moral concern. As I believe the purpose of morals is to promote the flourishing of our kind as a social species, this kind of moral overspill is morally significant. So torturing animals is not immoral as an act in and of itself, but encouraging and promoting animal cruelty does have peri-moral significance. I don't really care if little Johnny tortures the neighbor's cat, in so far as it is a concern solely about the neighbor's cat; I care about what it says about little Johnny. In addition, we may as a species be interested in promoting behaviors which are not in and of themselves moral concerns. For example, being a civic minded citizen isn't necessarily a moral obligation in and of itself, but we may nonetheless desire to promote it for non-moral reasons.