It's not like there isn't a middleground. I didn't see those awful sixpack rings in years, in Germany where I live those sixpacks are packed in cardboard (goes around the sixpack once for stability). Works perfectly fine, and given it's just paper with a little bit of printer colours (which, technically, could also be done environmentally friendly) there are little to no reasons not to do it this way except for greed. …therefore it isn't surprising plastic sixpack rings are specifically common in the US, lol.