My own reason, and then a few responses that should help people:
1) I've never spent enough time in BT to really know much about the invasions. I always seem to land there right after the invasions finish, and even then, for no great length of time. In a small(ish) niche community like ours, your readership potential goes down dramatically when it's focused exclusively (and I don't see how it couldn't have been) on one of the multiple continents. Simply put, non-BT players will have much less interest. I may still end up getting it for a good read about a world I enjoy, but that's what's stopped me so far.
2) egamma is right. Amazon has Kindle-for-PC as a free download, so anyone can easily have a e-reader.
3) CreateSpace does an admirable job at Print on Demand books. Back when I was producing pen&paper RPGs, this is who we used. For a 50 page perfect bound, you could fairly easily make $1.25-$3, depending on distribution method (and of course list price could drive it up more) without any out of pocket printing expenses.
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