It has been asked whether King Hui's cook could not just as easily have been butchering a human being as an ox as an example of the harmony of Dao. Some who think of Zhuangzi as a radical moral relativist believe he could. The Zen-inspired samurai are offered as examples of those who followed such a path. Yet such questions and even the consideration of degrees of moral relativity, because they remain in the domain of right and wrong, entirely miss the point of Zhuangzi's apparent amorality. Zhuangzi's sage lives a "moral' life without any consideration of morality; that's the point. Yet there is no philosophy or religion so moral that human beings cannot use it to perpetuate their dysfunction; that is the nature of dysfunction.
Still, the cook butchers an ox, and for some, this is tantamount to butchering a human being. It is unlikely, however, that, apart from the fact that it is the work of the lowly, Zhuangzi's contemporaries thought anything of it. Times change; contexts change; and it is possible that today he would have found some other occupation to make his point. Or, perhaps not; such a scandalous expression of 'spirituality' would have been very tempting indeed.
Thus, the question arises whether Zhuangzi used the dao of butchery as an example of Dao-ful living simply because it was the activity of a lowly caste or also because it involved the killing of a living being and its dismemberment. Did he intend to scandalize us morally? As implied above, I do not think so; such an activity was likely taken as a matter of course in his culture and time. Nevertheless, if we are scandalized today, it can be profitably so.
Zhuangzi does not approach reality with a preconceived idea of what constitutes moral purity. He is willing to accept and "follow along with" yours. When in Rome, he might eat beef; but when in Delhi, he'd definitely try the dhal-fry. If he had decided on the basis of the many cogent reasons on offer to be a vegetarian or vegan, he would no doubt refuse the beef in Rome, yet without making of it an indictment of those who do not.
The dao of butchery speaks to the inherent messiness of life. Nearly all living things require the death or compromise in well-being of other living beings to subsist. Even the seemingly innocuous pines outside my window drop their highly acidic needles to discourage or destroy any encroaching interlopers. I harp on this messiness because it helps to illuminate the great moral ambiguity in which we dwell. As Zhuangzi tells us, right and wrong are so hopelessly entangled as to defy our attempts to disentangle them.
You can check out Scott's writings on Zhuangzi here.