interesting question. i'm sure i have checked prices other places for reference, if i don't already know.
have noticed, like others have posted above, that often garage sale items are priced below market for Klipsch forum members.
Have thought of this as a win-win, not only for giving a brother or sister a good deal to share the love, it's also a win-win. The seller does not have to contend with an unknown buyer on Ebay, which sometimes adds considerable stress to completing the transaction in good order.