It's human nature to want the highest price for your stuff. And if there are people willing to pay outrageous prices, well, so be it.
It's called the free market. Seller can ask whatever price they want, it's up to the buyer to either accept the price, or look elsewhere.
I don't see the problem here, and I don't see why so many people are bashing ebay. Ebay doesn't tell the seller what price to charge, and doesn't force anyone to buy anything. All they do is offer a service (yes, for a fee... because ebay isn't Santa Claus, it's a business) where buyers and sellers can meet. The rest is up to the buyers and sellers.