I can't say I'm surprised at the number of people testing out the game before deciding to buy. File sharing's a lot like radio in the era of cassette tapes. With a little patience you could sample an album for free and you could even get a copy of it for your use. But if you actually liked the music, you'd go buy the record so that you could have a copy without the noise (tape hiss, DJ talking over the beginning and end of the song, etc.).
Similarly, with file sharing, you end up wanting to buy for the book's convenience, you have to search for a copy that's complete and uncorrupted, etc. And, oh, how the record industry ranted against cassette piracy and how it was ruining the industry! (While Sony was selling those very same blank cassettes!)
File sharing's got some advantages for the cultural producer over radio: with radio, you had to pay to get radio play. (Today, it costs roughly 400 grand to get national air play for a song.) And, of course, it's easier to sample a wider variety of indie products through file sharing than with radio play (or Barnes and Noble shelf space).
Of course, it must be said: If you download, use, and never buy gaming materials, may you be covered with boils in your most sensitive areas. It's not like you're striking a blow against the MAN, the way you might be with Time Warner or GE. Piracy against a tiny division of Hasbro is the cultural piracy equivalent of purse snatching: lame and hardly the work of a criminal mastermind.