We all need to think again about food waste, of which the UK produces up to 20m tonnes a year. Every dumped meal represents unnecessary production, packaging, transport and refrigeration. If Britain buys unnecessary quantities of food in the global markets, it pushes up prices around the world. Of course it would be best if stores stopped overstocking, but waste is built into many shops' business models. If they want to offer an impression of abundance and freshness for every customer, even the last one of the day, they have to throw away the leftovers. I've eaten enough croissants from big supermarket chains' bins to know they aren't blameless.