<P> Dairies in the United States used the bags in the 1980s, but today are confined mainly to regional convenience store chains with in - house dairies such as Kwik Trip in the Upper Midwest and other boutique dairies . </P> <P> In the United Kingdom, Sainsburys began a pilot experiment on distributing milk in bags in 2008 in conjunction with Dairy Crest . It was originally targeted at 35 stores at the same price as a regular 2 - imperial - pint (1.1 l) plastic bottle of milk, the product was expanded through the North of England nationwide in 2010 at which point the bags retailed at a discounted price compared to traditional containers . </P> <P> In the UK, the bags are usually used in conjunction with a specialized plastic jug . The bag fits snugly inside the jug, one corner of the bag is secured under a bar at the front of the jug, and as the lid is closed the bag is pierced and a spout slides into the hole, allowing the milk to be easily poured and maintaining freshness . Doorstep deliveries in the United Kingdom are normally associated with traditional glass milk bottles, but the Dairy Crest / Milk and More service also deliver milk bags, and sell Jug - It brand plastic jugs specially designed to hold the milk bags . </P> <P> In Mexico, assistance programs and prior welfare and government social programs distribute milk in bags (1 l (1.8 imp pt) per bag) at very low prices . </P>

Why does canada have their milk in bags