The file is fungible and that's great, but the license isn't. It's still bound to Amazon/Apple etc. and you can't give it to someone else, without Apple's/Amazo

The file is fungible and that's great, but the license isn't. It's still bound to Amazon/Apple etc. and you can't give it to someone else, without Apple's/Amazon's permission. With CDs/DVDs, Walmart or wherever you bought the CD from, has no say onto what you do with it afterwards. Whether you give it to someone else, sell it, etc. Of course, if you have a perfectly fungible system, you could have websites where you are being lended a medium for a short time (e.g. one day) for really low amounts of money and of course this would be bad for content creators as it would dramatically lower the sales. However, that can be countered by other means e.g. minimum restriction on lending duration (e.g. one day) and fees that content creators get on ownership transfer and each lending interaction (e.g. 5% for the first 5 years after movie release, afterwards 1%).