John's not going to put his neck on the line for this, so this is a compromise.
How would he be putting his neck on the line? If XCrowd doesn't deliver, he just returns the money. What's the risk?
Anyway, I don't really see the need for Escrow, if you don't need the order money to fund production why not just let people buy when they're ready to ship? Why bother with the whole pre-fund escrow thing at all?
The only reason I can think of is to lock in sales in the event the difficulty goes insane and the units would no longer be profitable. If you're units are going to be priced at a rate that will make any money for anyone when they're actually released, you shouldn't any kind of long-term escrow.
At the risk of making another incorrect assumption, I'd agree it's to lock in sales, as whether people commit to pay by pre-order now, or order when goods are ready, Abdi and xcrowd cannot touch the funds. Therefore it makes no diffrence to xcrowd whether you pay them now or later when they have products in hand, it only affects the customers free choice in future as any monies committed now cannot be spent on competitors also promising to supply products in and around the same time.