The question is not a stumbling block, it is irrelevant. We can not do anything to change the instincts or behavior of a lion. We can only control our own choices and behavior.

Seeing an animal kill another still hurts, especially for those of us who are empathic and feel others pain. The difference is that humans have a choice NOT to inflict that type of pain onto other living beings. That is all I can do, so I do my part to not add any more pain to the world.