There may exist non-carbonated water in glass bottles, but non-carbonated water isn't that popular: In 2014, only 13% of water sold was 'still', but only 23% all water sold was sold in glass bottles [1]. Given that most still water comes in plastic bottles, I'd say the amount of still water sold in glass bottles is rather small.

[1] https://www.spiegel.de/wirtschaft/unternehmen/mineralwasser-...