This is nothing new - DRM already allows banning of digital material long before the Kindle came about. Back when iTunes was stilled DRMed Apple could easily have de-authorized all instances of a particular song and done the exact same thing. Having the file is a trivial detail - it's no good if you cannot access the decrypted material.
Personally I have faith. We have, in a few short years, progressed from the draconian DRM of iTunes to the non-DRM stores that both Apple and Amazon run today. We have also progressed from restrictive DRM measures on video games to the decidedly anti-DRM stance of major game publishers today.
We have proven that DRM can be defeated, so I wouldn't scream bloody murder just yet.