No, murdering other innocent beings to survive is not necessary, natural or normal, as much as murdering human animals is either of those. Actions are learned. Choices for survival don't mean something is normal, natural or necessary when alternatives exist.
The normal argument is all based on the follower mentality. You have to want to be a follower to accept that it is normal. It is the entrenched and instill beliefs of the dominator culture to make something normal. All you are doing by grafting onto that belief is accepting the belief system that is based in domination and violence as your own because you don't want to stand out and be a unique individual. You don't truly become vegetarian or vegan because of the health with trendy reasons. You do it based on truth and cosmic spiritual laws. When you realize that your actions are in opposition to those higher spiritual laws you cannot reconcile these things, you cannot say that I know that this knowledge with a deep understanding but my behaviors and actions are in deep opposition and that is okay. No it is not. We have to change ourselves in alignment with truth.
The normal belief of the dominator culture is based on follower mentality, group think and collectivism. It has no regard for the actual moral issues involved.
People believe erroneously through their religious belief systems that it is man's natural state to consume the dead flesh of other animals he has killed. They believe that is somehow natural order. That is the complete antithesis of the true natural order. This false belief in the natural order is a lie the linear progression of man's evolutionary progress on earth and is based on Darwin's theory, the notion that the species with biggest claws and teeth come out on top. The most conscious being is the highest expression of nature's order, not the most vicious being which probably pulls back evolutionary progress the most, the beastial form of consciousness.
Part of the argument is that we see other animals that it is part of their nature to eat other animals so why shouldn't we do it as well. The first answer is that we are not the same kind of animal is them. It doesn't make a difference with somebody else's doing. Same argument as just following someone like following someone who's jumping off a bridge, would you go and do that. It is that same level of retardation and stupidity to do that practice simply because it is being done by those lower than you. Animals are a lower form of consciousness than human beings.
There is a differential in conscious awareness in nature. There is such a thing as different levels in different places we are in consciousness. We have the potential and we should be at a higher level of consciousness than animals [but we currently lack compassion and honesty]. We are part of the animal kingdom, and are and expression of animal life, anima, imbued with the soul. We are different in the plant kingdom in that regard because it is more directly linked to the earth soul. We are individuated expressions imbued with movement, we are not grounded in the earth and insulated. We can move freely on the earth. That's what makes an animal different than a plant.