I also rarely buy books. !st reason is lack of space for a library. 2nd, is that with my deteriorating eyesight, I'd need all of them in large print. So, I use my kindle more and more each day. If the font is too small, I can increase it. If the font is too hard to read, I can change it. And, the storage space is minimal.
Many paperbacks are way too small print for me. Even many of the larger books have fine print. Fine print that might not fe fine to you can be unreadable to me. Again, this doesn't happen with my Kindle.
Only problem I've seen with my Kindle is that most of the free ebook sites that I've found us the EPUB format. And, my Kindle can't read that. They tell me that an ebook in MOBI format can be read, but, so far, none of the ones I've "sent" to my Kindle have even appeared on it. Let alone be able to read it there. Been told that just transferring a MOBI ebook to my Kindle is fine, that Kindle can read that. But, I haven't tried that as yet. Want to know more about it before I simply copy a MOBI ebook to my Kindle. Downloading a Kindle ebook from Amazon works fine, but, Amazon sells Kindle and they probably know more about what is needed for the download than I do.