I know you didn't...
I know you didn't ask, but somebody did, so I'm answering the question, Why do you give away all the royalties from your books?
Long answer: I'm not by nature an unduly generous person. I have a few loyal readers but the books they buy don't generate enough income to augment my lifestyle, which is simple as much by choice as by necessity.
Books sales unavoidably influence an author's work, especially once you get a few. If I give away what I earn as a writer, sales are the publisher's preoccupation, not mine, and I'm free to write as I please, at least, until Editor sees it.
Short answer: It is more fun to write for love than for money.
Thanks to John Paul Krol for the photograph.