Flash shop

Have you heard about the flash shop (also called the cash mob)?  It is a cross between a flash mob and a social coupon (Groupon).  A bunch of people all show up at once at a store and get a discount.  You might think it was sponsored by the company (like Groupon is) and there probably are some of these.  But the person who (claims to have) invented it says he picked a local store he liked.  Partly just for fun, partly because he is a “shop local” guy, and in part because he likes the store (it was a bakery).  He sent the invite around to his Facebook friends and Twitter followers and they negotiated the discount with the store owner in real time when they all showed up.  They bought stuff that was already on the shelf, so it was smoother than a Groupon for the store. 

Is this a better user experience?  More user-friendly?  Better business?  There is a lot to think about if you want to do something this as new sustainable business model.