I think it may well be for many. If one were to kill a person in a drugged state would it be morally upright as that person had no ability to complain ? Is it your contention that killing something that simply has no capacity to communicate their distress is morally superior to killing something that can show you how distressed it is? If an animal were sedated to the point of complete unawareness would you find it as morally fit to kill it as you find killing a cabbage to be? Do you have a hierarchy of the living i.e. are some of the living entitled to take the life of others of the living in order to eat? If so, then how do you determine which of the living each particular class of the living can morally feed upon? Should a leech, for instance, be morally ashamed for feeding upon a class of living beings that are more advanced than itself? I have a bunch more questions I would like raise on the subject but I am already becoming too wordy here.