I wanted to elaborate a little bit more about ritual slaughters that were performed in the Tabernacle. I've discussed this issue in this post before, but I wanted to give another (better) example of why the slaughters were needed and why they are logical and justified.
Consider such example: Your child has a throat cancer and needs a throat transplant or he will die. Throat transplants are hard to find, so in many cases modern medicine uses substitutes from animals, usually a pig or a cow. So, is it justifiable to slaughter a cow to save your child? Of'course! Especially if you will eat remaining meat. This is hopefully clear. But please note that in order for your child to live, someone (a cow) must die.
This is why we have slaughter system to atone for sin. Somehow our sins are forgiven if we go through specified slaughter rituals. They work just like an example above. Sin is a "throat cancer" so we slaughter a cow to atone (get throat transplant).
Like I pointed out in the previous post, the meat of the slaughters was not burnt, it was given to the Levites as food. So Torah slaughters are not sacrifices, but rather a glorified slaughter of animals for food. This is why Torah is not a religion.