Whilst I think it just has to be accepted that Apple control the software on their devices quite 'robustly', I really can't see how they can justify saying that you can't get a piece of hardware that you have purchased and therefore are the legal owner of, repaired wherever you like, especially if genuine Apple components are used. Where could this lead to next? If you buy a motor vehicle, would it be acceptable if the manufacturer banned you from doing any work on it yourself, or getting a third party to service it?