Because he just set up the ebay profile on August 21, 2010. He put up one auction for the item with multiple qty available. Starting on August 22, people started making purchases and there won't be any feedback until those people get their items.
I think it's pretty crazy that so many people are willing to buy items from a seller with no feedback, but it happens all the time. It's a really good price for the item so people are jumping on it, they probably figure if they don't get it they'll do a chargeback on pp.
For the price he's offering and having such a large qty available, my guess is that they're pirated dvds. I imagine the sellers account will be closed once the first person complains to pp or ebay.