Really, a virtual economy where items only become less valuable over time (like .moar files) or remain at a fixed price (like all of the items in NPC shops), is really, terribly stale and uninteresting. Things have to be able to change in price, both positively and negatively, in order to really call it an economy. When formerly rare and expensive things can become widely available and inexpensive and formerly commonplace items become rare and valuable, that’s what makes virtual economies interesting.

If nothing other than headsets and the falcon plaque are ever “luxury items that not everybody can get” there’s really no point to having kyoubai in the game. And those are items that exist in quantities of less than a dozen. It would be nice to have a few desirable luxury items that there are a few hundred of, so even new players could have a reasonable expectation of acquiring a few of them if things break their way.