I just wish Club Mate was popular in the states. I love it and it's super popular in Berlin but I have yet to introduce it to a single person in the USA who like it (T_T)
A few years ago there was a real boom with many small soda companies/startups popping up to challenge the Club Mate hegemony with their own Mate brews. Many disappeared again but some did stick around, so there is still a good variety in Mate vendors.
There are still many rather small operations too [1][2], so entering the soda market doesn't seem to be that hard compared to other things. And having a product that's mildly addictive is good for customer retention.
[0] https://www.flinkeflasche.de/categories/52 [1] https://kolle-mate.de/ [2] https://www.flora-power.de/