Now that Desktop Dungeons has released on Steam and is likely to see a much wider user base, I recommend retagging desktop-dungeons-paid to simply be desktop-dungeons. The other tag is desktop-dungeons-free, so either way it should be clear which is which. A good tag wiki should clear up any possible remaining confusion.
Anyone coming to ask or search for questions about the game is likely to simply type in desktop-dungeons. We also don't add paid to any other game that requires money to play but has a free version or demo, so our current tagging is a bit inconsistent.