Production Motivation

I started buying juice shots and noticed that Solti is a company that markets their bottles as sustainable because they are made of glass. There are also many similar companies that sell the same thing but with plastic bottles. My question is if the danger of petroleum based single-used plastic packaging is now known to be harmful to both humans and the environment why then don't these companies switch to glass? I know the obvious answer is if the consumer buys it then they will keep producing, but is there any other motivation to them not switching to glass? It seems like the companies are blatantly showing us they don't care about our health or the environment but we still buy from them.