It seems as if you're attaching the same connotations to morality/ethics as you would to legality. If something is not perfectly moral/ethical, it doesn't mean you should never do it.
We over indulge, we waste electricity and water, we drive unnecessarily big cars because it's enjoyable. It's not moral or ethical, but it doesn't make you a bad person. When it's done en-masse, is encouraged, and corporations monetize it, is when it starts becoming a problem.