Yes, it's not particularly ecological, but I found that I'm able to focus at the text much better this way. My Kindle (despite plenty of obvious advantages) just doesn't really work for me.
It took me years to realize this, but I always start to tinker with the brightness settings, switch pages back and forth, go into the book library and back, play with highlighting words, etc. I will do anything instead of reading the text. Meanwhile with a paper book I don't have an urge to flip a page back and forth and observe how it behaves. I can focus on the text.
Not sure why I am this way.