Amazon dominates the e-reader market, and for some people that’s just fine. But buying a Kindle means buying into Amazon’s ebook ecosystem. You’re stuck paying Amazon for books until the end of time. Most of the money you spend on books from now on will go to Amazon, a power-hungry behemoth that treats its workers poorly, and very little of your purchase will actually support the author whose work you’re enjoying.
But it doesn't have to be this way. You can enjoy ebooks and ditch Amazon for good, too.
Kindle is pretty tied by default to Amazon (it won't import and read popular ePub or Adobe DRM formats without using Calibre to first convert them) whilst most other ebook readers support quite a variety of popular ebook formats (apart from Amazon's format of course which is proprietary). Other ebook readers in fact also have a lot of additional features, and it could be argued even that they offer better value than Kindles.
So often the issue comes down to the selection of books. Certainly with the first option listed in the article below you do have a pretty big selection of books including some I don't even find on Amazon. Nice thing with these books is you are not locked into a particular brand of ebook reader either.
See How to buy and read ebooks without Amazon
There are much better ways to read digital books than what Kindle has to offer.