One problem is that we don't know the full cost, including the environmental impact, of each option. Glass can be cleaned and reused, but it's heavier, so tran

One problem is that we don't know the full cost, including the environmental impact, of each option. Glass can be cleaned and reused, but it's heavier, so transporting it both ways results in increased emissions. They could also choose to use reusable plastic containers (soda companies did this in Norway up until around 5-6 years ago), but collecting the used containers takes up much more space if they can't be compacted, which I think some grocery stores do now. There's quite a bit of energy that goes into washing containers as well. Supposedly sometimes more than what is required to manufacture new ones. I'm not sure we as society are really able to quantify the environmental costs of each just yet.