Having recently sold an iPhone on eBay and been concerned about problems like this, I wish eBay would allow non-professional sellers restrict bids to professional buyers.
If they were to let me limit sales to people with certain types of addresses, purchases of certain value, a reasonable number of feedback, etc, that would be very helpful in reducing a chance of being defrauded
In fact, when I was placing my first bids on eBay, some buyers would cancel the auction or retract the bids because they didn't trust me. I understand their position, but how are you supposed to get feedback if sellers won't sell you anything?
If you sell, say, more than 500 items a year, you turn into a professional seller and you can't be as restrictive, but you are doing enough business for the occasional scammer to not make a large impact.
Of course, I think eBay is harmed relatively little by scammers like the one in the OP; so I can see why they haven't done much to prevent it at risk of loosing real business.