I keep seeing this posted and have never seen a source for it. I don't mean to challenge you or call you out in any way, but do you have some source for the claim that Apple replaces all these components you mentioned? If someone returns their MacBook after ten days because they did not like it, why would Apple replace all the components you listed?
I would think they would reinstall the OS and run diagnostics and clean it up, then sell it as a refurb.
I thought the same thing, unless there was an issue with it; I figure they'll do a full inspection, of course, and get that Inspector 42 seal of approval, but unless it was returned for cause, I don't assume anything. Besides, it's on a full warranty.