Presenting oneself as ethical may get one the support of (i.e., power over) those who believe in morality. And believing in it, i.e., unconsciously lying about it (to oneself and others), is a consequence of the will to power: as Nietzsche says, when something has a greater effect if unconscious, it will become unconscious. So those who believe in morality do so only to increase or consolidate their own power.

Why acquire power? What is one to do with power? I think all power is the power to will. So the will to power is really will to power to will to power etc. But will is a pathos, i.e., something passive - a passion. But this passion can be enjoyed or suffered. A human being is really like a conscious stone. The stone is rolling downhill, and can do nothing about it, but it may think, and feel, that it is in control. It is this feeling which is pleasurable. The stone may say, "Yes! I'm rolling downhill! That is precisely what I want to do!", or it may say, "Oh no! I'm rolling downhill! I don't want to! Help!" The former is self-affirmation; the latter is self-denial. And there is no free choice between them. But the denier also denies his own denial; whereas the affirmer affirms his own affirmation. A double negative is a positive, but a double positive is not a negative. So all existence is positive, even though it may seem negative from a negative perspective.