If you have an account at the library and strip the drm, read the book on your kindle, then delete the drm-free copy, I really don't see an issue.
The issue, for me, is that doing this is illegal. At least that is my understanding of the law. Call me a goodie-too-shoes, but I don't wan't to break the law. Yes, it is small and I doubt anyone from the FBI is going to be kicking down my door if I strip the DRM but that doesn't mean that it is legal and allowable.
I understand that there are others who view it as you do, and that is fine. You have to do what you are comfortable with. Some see it as legal now based on the recent ruling but I don't read the ruling that way.
My understanding of the ruling was that Text To Speech on the Kindle could not be blocked for people who are visually impaired and who do not have access to the book in some other format. So if the book could be read using software on a computer/Laptop/ different e-reader then the DRM could not be hacked.
I do not think it said that all DRM could be stripped.