In the USA, the last weekend of November begins with Black Friday. Stores open early, offering extreme discounts; shoppers queue for hours, waiting for the spree to start. Almost half the population of the world’s wealthiest (and third-biggest) nation joined the three-day frenzy last year, bringing in US$11.4 billion of business. But bargain hunting can be brutal. In 2008, Walmart worker Jdimytai Damour was trampled to death by 2,000 shoppers as they smashed through the store’s glass doors, moments before they were due to open.