Angry With Digital Copies of Books

I got a job recently where I can basically read once I get all my work done and I'm a bit mad with services like Amazon Kindle. Why are there some books that I can't get digitally? Like I really want to reread some of the books I read as a child, but there are some that are only available in physical form, some series that are partially supported in digital, and some series that you only get some of the story and the rest is just "fuck you we don't want to publish this digitally". I want to go through and reread stories like Daughters of the Moon by Lynne Ewing but only 6 of the books are available digitally in 2 box sets or the Zodiac Twin Flames series by Rachel Medhurst which seems to have disappeared from amazon. Like yeah, I found some good books I wouldn't have found otherwise and physically having books is a good thing, but I don't have the space for books I want to read and can't carry around a physical book with me everywhere so I can't really do the library thing for reading. Kindle has been good for me and I wish I could get more from kindle.