Huh?

I have my third book, Write Now! The Prisoner of NaNoWriMo, for sale as both an ebook and a paperback. If you go to Amazon, it costs $13.99. If you ask me nicely, I'll probably give you a copy free. Why then on Amazon are there two listings for "Used" copies starting at $42.56? I wrote the darn book and I wouldn't want anyone to spend that much! [Well, maybe if they really wanted to, and they had, say, cash - but that's a specific subset not on-the-table for discussion here, now] What are they, first editions? Wait, they're ALL are first editions!! Oh my.....