Two years ago, Unilever plc Chief Executive Alan Jope said his company would get rid of the tiny plastic packets it uses to sell single servings of shampoo, toothpaste and other basics because of the widespread pollution this packaging creates. These palm-sized pouches, known as sachets, are commonly associated with ketchup or cosmetics samples in wealthy countries. But they have exploded across the developing world where they are used to sell everything from laundry detergent to seasoning and snacks to low-income households.