You rang?

I believe you're referring to the ebay seller 'classical enthusiast', who tends to list several hundred auctions at a shot (literally, ending within the span of 10 minutes in a veritable blizzard of un-bid items).
The vast majority of the discs this seller lists seem to be currently in stock at the Berkshire Record Outlet, for $1.99 or $2.99. If a given CD takes five listings (at a minimum bid of $6.99) before there are any takers, well, five 30 cent listing fees still gives a profit margin of around 100%. My guess is that either the seller *is* the BRO under another name, or someone who haas arranged a deal with the BRO to sell their discs on eBay.
Disclaimer: I'm an ebay seller myself, though I go in much more for rare one-of-a-kind discs (I just managed to track down a Moscow Autumn Festival CD of Eshpai's 6th which I never knew existed!)