I don't see why we should kill animals to eat when a plant based diet is viable and nutritionally complete. In the society that we live in, we don't need animal products. It is also terrible for the environment and uses up a lot of the worlds resources.
You asked why should we kill them, well first of all meat is delicious and a good source of protein. Also, when you eat plants then you are killing the plants too. Also, exotic meats are a huge part of the economy. I hunt squirrels, and they are good. God gave them to us for food and for natural beauty. Therefor, i go against veganism.
However, plants aren't sentient beings and they don't feel pain. Plus, animals eat plants as a source of food, so either way you are going to be "hurting plants." Meat dosen't taste good on it's own, it's just seasoned well and has a good texture. There are also way more sources of protein then meat.
"Your righteousness is like the mighty mountains, your judgments are like the great deep; you save humans and animals alike, O Lord." "Psalms 36:6