This is a story from the US, but if they are successful, it could start being used here, which would mean an end to successful misprices:
"On December 23, Amazon advertised a 'buy one get one free' sale on DVD box-sets, but apparently did not test the promotion before going live. When anyone placed two box-sets in their cart, the website gave a double discount — so the 'grand total' shown (before order submission) was $0.00 or some very small amount. Despite http://amazon.com/gp/help/customer/display.html/002-3504943-4261604?ie=UTF8&nodeId=468502#confirm
terms stating that Amazon checks order prices before shipping , Amazon shipped a large number of these orders.
Five days later, after orders had been received and presumably opened, Amazon emailed customers advising them to return the box-sets unopened or their credit cards would be charged an additional amount ( http://forum.dvdtalk.com/showthread.php?t=491165
threads ). Starting yesterday, Amazon has been (re)charging credit cards, often without authorization . On Amazon's side, they didn't advertise any double discount, and the free or nearly-free box-sets must have cost them a mint. But with Amazon continually giving http://www.fatwallet.com/t/74/702422
unadvertised discounts that seem to be errors, is 'return the merchandise or be charged' the new way that price glitches will be handled?"