If you learn about an item through the auction, then eBay prohibits you from making a deal outside of eBay. In this case, the item has been posted for sale here for two months, so it would be hard to argue that case.
Also, the seller can choose to sell to the high bidder at any time. eBay is happy with that as long as they get their fee. People still let auctions play out when confronted with a reasonable offer. For some, it is a lack of understanding of the rules, some a feeling that they are honor bound to let it run out, and some just are greedy and want that max bid.