@PNS @Jagahati
Up to a few years ago they had them
https://www.reddit.com/r/nostalgia/comments/yh1vhk/i_remember_those_frosty_rootbeer_mugs_you_could/
Scroll down a bit where someone from Albany OR says how much they are etc.
I lived in that area in the 1970s & just got the paper cups to go. You could buy a quart sized milkshake back then. Never bought the glass mugs.