Is it the way animals ARE killed that worries you or the fact that they are killed full stop.
For instance if you saw a cow get killed, instantly with little to know pain would you any problems with that? I know it's off topic, but i'm interested to hear the answer
Although this wasn't aimed at me I'm going to throw in my two cents.
It's both. I have massive problems with the way that many animals are raised and killed. More than that, I have a problem with the way that animals are killed and the fact that there are people who believe that by buying small, independent farm organic meat they are somehow getting an ethically superior product. Yes, in most cases these animals live 'better' lives, but the are killed in the same slaughterhouses, with the same violent and horrific means.
Second to that, the biggest problem that I have is with the use of animals full stop. I personally, as a vegan, do not believe that animals are here for human use. That's not just food animals, either, but ALL animals (which is why I have a problem with zoos, like many others on this site).
Long story short: Animals aren't ours to use or manipulate, they're not here for our entertainment or our consumption or our safety.