Well i believe it comes down to reducing waste and increasing quantity that can be shipped at once.
To create one of the jugs you guys have... in order for it to be safe to hold a product for human consumption you need to have a certain amount of new plastic mixed tithe recycled stuff to make the jugs. Our bags use less plastic to make so they create less waste.
In one of our 2x2 milk crates 4 of these bags as they are flexible. This increases how many can be shipped at once.
Another advantage since i have had this happen to me before is if by chance a puncture occurs in the side of the jug, however unlikley, like i said it has happened to be before. I lost and entire gallon whilst walking my groceries home, if i would of had a 4L bag that puncture would have only cost me 1/3 of my milk.
Neways out of the different form factors i prefer the bag system, guess i am just too Canadian for my own good.
Any other stereotypes you guys want cleared up...lol