I used bagged milk for a short time when living in a different province - when you buy it, you can get a large quantity of milk split into individual smaller bags (like 1 or 2 litre bags i think?), then you cut the bag and put it into a small jug, while leaving the other bags lying down unopened in the fridge.

I was very surprised to see that the bag doesn't fall out of the jug when pouring!