Why is cubivore pricing totally off eBay and amazon

Can you give me more details on what you mean?  What ebay and Amazon prices are you comparing?

I'm guessing the difference you are seeing is comparing sales prices to list prices.  On rare games, active listings on eBay and Amazon can be quite a bit higher than the actual value.  The listing price is only what the seller wants.  It does not indicate a buyer is willing to pay that. We only record prices where a buyer and seller agreed on the price (an actual sale).  This value is much more accurate than a list price from the seller.