[cauliflower2718]

Just speculating about orange juice: vitamin C degrades easily when exposed to light, so that orange juice in clear containers lose more vitamin C than orange juice in opaque containers. That could be one reason against (clear) milk bags, but there are certainly clear bottles of orange juice sold, and I suppose you could use opaque juice bags, though those would be less user friendly than clear juice bags.

Edit: capri sun juice pouches!

[joker_minmax]

Orange juice is nearly always sold in a clear jug in the US, and that which I can remember in Canada. In fact I don't think I have ever encountered an opaque jug of juice, only paper cartons.

Also, Caprisun pouches have foil backing that cause them to somewhat maintain shape, and a design that gives them a base to stand upright. Canadian bagged milk, at least what kind I encountered when I was there, had neither of these traits.