you should see the carboard framed plastic bags they put most of the milk in here on Madeira, and I only really noticed it recently because it is so cheap, and I needed to dial down my costs.

Note that the cost of the packages is incredible. The carboard framed plastic bag version at 200ml costs basically half of the cost of the 1L carboard framed plastic version.

I'm not sure that the economics actually add up in this case. By that metric, it looks like the milk must cost about 20% of teh price of the product. The bag option seems to me like it's going to have false benefits because the cost of holding in the weight of the material relates to the amount of energy that is required to make it. The old school glass milk bottles were used hundreds of times before they were broken or lost. They tended to exceed the amortization of their initial energy inputs. The cost of making plastic strong enough to hold this much material I think it already got played out with the polyethylene based bottles that were normal until the 2010s or so. They fail beacuse they have a high cost of disposal! The same thing applies directly to the bags, because the cost of production of a high tension capable material like this versus a lower density equivalent tension capable material versus a far more durable one that you avoid throwing away... do the math.

This is just an example of how the climate cult warps the market with false and perverse incentives.