The row has broken out only days after James Daunt, the managing director of Waterstone’s, criticised Amazon – calling it a “ruthless, money-making devil”. The new Amazon Price Check app and promotion, which is starting from this Saturday, will allow people to perform a price check on an item in a shop, by scanning in the bar code using the app on their iPhone or Android device. The online retail giant will then offer a $5 discount to shoppers who carry out this market research for it for free, on any item across the site, including the same item they...