I read an interesting post on Pamreader yesterday: is supporting an author just about buying books? No, it's not. That's just one of many ways in which we show appreciation to the authors we enjoy.
To add my personal spin: a single sale means very little financially - I would need many thousands to break even on a novel - though the sale means something significant to me emotionally, since someone has been interested enough in my writing to spend money on it. Book sales certainly aren't the whole story though. A single favourable review or comment means loads. My days are always brightened when someone says something nice about my books or writing. At present that’s one of my key rewards: connecting with people. That’s why I happily give away my books (often print copies) because finding readers who enjoy your work is why writers press fingers to keyboards. So thanks to all fans of writers and book bloggers who say nice things and make it all worthwhile. I can’t emphasize how important that is.
I plan to do a blog post about finances in the future - to counteract the view that published books = money rolling in! Since I started writing I'm probably about £20,000 down from if I had just done a normal job, and if you take all my income from writing over the years, and take it away from my expenses (research, cover design, editing services, proof copies etc) then I am probably on -£6,000 or more. Yes, that is a minus symbol! So I'd have to avoid spending a penny and sell over £6,000 books just to break even. Eek! Good job people who appreciate my work and write about it make it all worthwhile. :-)