I grew up with bagged milk but don't have it where I live now. With my two kids and I enjoying breakfast cereal regularly, our recycling bin fills up fast. I miss milk bags. So low waste. I remember we'd slit the end and use them for sandwich bags in our lunch bags. Or use them to wrap blocks of cheese.
I swear I remember my mum freezing sealed bags of milk for the cooler to keep meat cold on the way to the cabin.