We have lost no freedoms. Using a Kindle and subsequently agreeing to the terms of service are voluntary. If you feel strongly about sharing books, don't use ebooks.
For the content you want, there may one day be no alternative, but I find it unlikely. The trend through all of RMS's posturing and windbagging has been more and more free exchange of information than there ever has been.
I understand what you're saying, but I feel like I should point out that there is a very large corpus of ebooks available that are not customer-hostile. (feedbooks.com, pragprog and oreilly, etc.) In fact, the Kindle hardware works great with them. It's only content purchased from Amazon which is objectionable.