We still had glass cola bottles and recycling of same when I was in high school in the mid 1970s. I think they switched over to plastic bottles in the late 1970s or the 1980s. I remember putting our empty cola bottles back into the six-pack carton in which they were bought and returning them to the store for the nickle per bottle refund. I also remember and old retired man who lived at a nursing home in my town. He was old and forgotten by his family, but he was still healthy and energetic and we would see him walking all over town gathering up empty cola bottles to raise a little spending money. Later I found out that he gave that money to fellow residents at his nursing home. We called him Coke Bottle Joe. Everyone liked him. I hope he wound up in a special place, if such exist, as he certainly deserved to.