In Massachusetts the last glass recycling plant closed a couple years ago. The main problem glass bottle demand was down and the plant making the bottles closed ( beer being more popular in cans is cited as a cause)

https://www.wgbh.org/news/local-news/2018/07/19/massachusett...

They've been using the ground glass as aggregate in roads..

You are 100% correct in that there needs to be economic incentive.