I think there are a lot of reasons. I'm not vegan and I'm not a vegetarian but I always keep in mind that there a animals which will be grown up in bad circumstances. They only live to die and live to give milk or giving eggs. I think that's not cool and everybody should think about that. When they buy meat for a small amount of money. Many people say this is a nogo.

On the other hand you can see the ecologic side. We feet animals with food that we also can eat. I heard that 80 percent of the world cereals given to animals as food. That's totally crazy if you ask me. Think about it.

There is also a very interesting documentation that I recommend. Its called "Home". You can find it on Youtube.