That is the question University student Sheryl Ng tried to answer in her video How Canadians Drink Milk (not an accurate title, since in Western Canada you can't get bagged milk.) We have covered the issue of milk in bags before; Collin wrote Forget the Jugs; Milk Bags a Hit in Canada, UK last year. Much of the world gets their milk this way, from China to Argentina to Eastern Canada. It uses 75% less material, and the bags can be reused as sandwich bags So why does it stop at the American border?
The Star explained the history of it; It appears that you can blame (or credit) the metric system.
It appears that DuPont brought the system to Canada in 1967, but didn't catch on; most of us were using reusable plastic jugs. The milk companies hated this, and put out stories about mice and chemicals and all kinds of other things coming back in bottles. When Canada went metric, it would have cost a fortune to retool and replace all of the bottles with new metric sizes, whereas it was just an adjustment on the bag machine to go metric. The jugs just disappeared from the shelves and now 80% of Eastern Canadians drink milk from bags.
Because the packaging is so minimal and light, some say it is more energy efficient than recycled glass bottles; In the UK, the switch to bagged milk is expected to keep 100,000 tons of plastic out of the landfills.
It is cheaper too. Why don't they sell it in America?