You do know about the auction site, don't you?
Why is this interesting? There are a hundred auction sites and most of them are crap. eBay isn't even an auction anymore with buy it now and things like quibids are complete scams where you have to buy bids.
Ok, having looked at the auction site I can see why this may contribute to the price increase-- although it is sure to fail.
1. The auction site has a very few listings, mostly worthless baseball cards but there are 2 sets of items that may be driving up the price:
a) cars listed at 1500 UNB and b) $1000 gift cards to walmart or bestbuy listed at 525 UNB.
Whoever is selling a car or $1000 gift card for 25% or less of its value is either a scammer or an idiot.
BUT if the price of UNB is bid up so that the discount is very small that may work.
This is sure to fail however. Why would anybody want to sell something for UNB instead of dollars unless they could use those UNB to buy something else- and for now they can't unless they want to sell a car to buy gift cards.