I have a hard time cognitively justifying most physical book purchasing anyways when internet shadow libraries have most of what I want to read.
But if you do have the means, drop the author some bucks for their work. And I can assure you, it's a lot of work. My tip jar doesn't get a lot of action, but when it does, I'm very appreciative. Here's someone who appreciated the work enough to drop me a few dollars for my labors when they didn't even have to.
https://pages.cs.wisc.edu/~remzi/OSTEP/
The above is another example I appreciate: the authors charge for physical copies and complete documents but generally make the work content available for free. I've bought a physical copy in that case because I really valued the work.
I read a lot on my old Kindles, had a gen 1 and gen 2, it was easier than on a computer but still not the same experience as a book. Years later I had read many books on Kindle that I'd mention to people and... I could never let them borrow them, having physical copies also lets you share your favourite books to people you like.