nijuu: Getting both is just plain greedy IMHO
Why? I want a game on Steam for easy access to patches, and I want a game on GOG for easy archiving. It won't be the first game I have two copies of, and I do use them both. Same as HB, you get a steam key and a drm-free installer.
If people wish to keep one and sell/trade the other, yes, I do take offense at that, but I don't want to limit my choices.
Edit: I also love that they give their kickstarter starting time in the "PlaneScape: Torment" timezone (yes, I know PST is Pacific Standard Time, but it does make me smile).