Taking advantage of this "deal" is obviously morally untenable if you stop and think about it. Rather than posing the hypothetical of flipping it around between

Taking advantage of this "deal" is obviously morally untenable if you stop and think about it. Rather than posing the hypothetical of flipping it around between vendor and customer (i.e., "Would you be OK with it if Amazon charged you more?"), consider the case where it was a local mom and pop camera shop that made this mistake on its website. Then you would probably feel terrible about exploiting this and would be fine with the company requesting the merchandise be returned, say with a $100 store credit. Now ask yourself why this scenario is really different from the store being Amazon from a moral standpoint. If you're being intellectually honest with yourself, you will conclude that it's the same reasoning that would support the idea that it's OK to steal from people as long as they are very rich and won't miss the money.