For what it's worth I saw more of them in Kyoto than in Tokyo. I was staying around here: https://www.google.com/maps/@35.0086507,135.7541648,17.51z

It did bother me that I could never tell what the actual size of the drink was going to be. Is it in kanji, or is it just not listed at all? I definitely had a situation where I was expecting a full normal sized bottle of green tea but got a smaller one.