I have a question regarding "Private Auctions" on ebay.

Below is a link to an item presently being offered on ebay of which "21 bids" have been received so far ... or so it says. The seller terms this $1 chip from San Juan Hotel in Puerto Rico as being "rare"... which I do not disagree with. It's a very seldom seen chip and probably well worth the current bid.

My question is ... what benefit is there to the buyer and to the seller ... and to unsucessful bidders for that matter ... when the identity of the bidders are concealed? I would want to know who I'm bidding against if I were interested in this item and if the bidders are "real". How does anyone determine if all these "bids" are legitimate?

Currently, the top bid is $256 ... which has not reached the reserve the seller has placed on the chip.... with an opening bid of .01 cent.

What are your thoughts on "private auctions"? What has been your experience with ebay's Private Auctions? If this feature is so good, why aren't there more of them? Seems to me that private auctions would be a shill bidder's paradise. No, I'm not suggesting that this auction I've cited has any participating shill bidders ... but how would one know that, if all the bidders identities are "protected"?