I don't see how it can help buyers for the reasons listed. It's annoying as a seller too because I tried to price my stuff in line with recent sales to move them, so it increases the guess work needed.
If this is permanent, watch for a premium "service" they'll offer that will allow you to view the actual price.
I have heard there is a crude workaround that could be somewhat useful if there have been several sales. Sort by price and the completed listings will be sorted by the actual sale price. You still can't see what it was, but it will at least give you a top and bottom range (if you're lucky).
My sketch collection: http://sketchcollectors.com/gallery.php?user_id=727
I'm offloading my sports cards for cheap. Check out MonkeyLots in a B/S/T forum near you!