Firstly: just because something behaves in a way doesn't mean we should do it too, or not. It's not relevant to the decision making process, as we are not eating them for what they do, but for what they bring to us. We are intelligent creatures capables of decisions based on something else than instincts, and this should be one of them.

Secondly: our technology allow us a variety of diets and ways of life that the animal primitive way of living does not.

This does not mean you should be vegetarian. I am, and I would certainly not enforce it on anybody. But if you take the decision to be veggie or not, it should be from the perspective of a modern, educated human in the context of our science and society.