Because you aren't buying an ebook, you are licensing a copy of it. The terms of the license you agreed to were that you will not distribute or re-assign ownership of the material you are licensing.
If you want that to change, you'll need to get congress to do something about it (lol).
We as a society very urgently need to ban the practice of "selling" licenses, but in the meantime we as individuals can and should practice civil disobedience.
If you want that to change, you'll need to get congress to do something about it (lol).