Ask HN: What are your book purchasing and sharing habits in the digital age?

When I was young, my dad had a floor-to-ceiling built-in book case full of books. Most of them were uninteresting to me as a child, but over the course of my childhood I picked up a lot of interests and ideas from these books. It's safe to say they had a significant influence on who I am, and instilled in me a love of books.

In the age of Kindle, Audible, et al., what are your habits in the area of purchasing and sharing books? My approach is to buy most books in digital format, especially in audio as I drive quite a bit, and then purchase hard copies of those books which are most influential that I might want to share with the important people in my life.

Perhaps building a small library is not even the optimal approach. For instance, I recall that personal finance guru Dave Ramsey says he would pay his kids non-trivial sums to write a book report on books which he wanted them to read.

What would you consider the best practices in this area for maximum benefit to others, especially one's own children?