I'm the only one making my own carbonated drinks? I've had a Sodastream for a few years, but I used it so much that the plastic lever broke, still usable just pressing directly on the valve. I probably drink 90% straight carbonated water but I've used a lot of those Mio flavor & similar competitor flavorings; like Crush-grape-strawberry-orange, & cheap locals like Walmart's great value flavors.
The upside is no or low sugar, no corn syrup or other crap-as in the ready made sodas. but dang I've always liked the feeling of drinking any soda, unless I think it tastes not good (like Pepsi), swishing it down. It's also nice for alcohol mixes, the best flavor I think for that is Mio's orange-vanilla.
The full flavor syrups Sodastream makes are alright too, then those have more sugar & whatever else in it depending on type though. I'll probably buy another one or similar product if I need to, they're cheaper in the long run.
It's likely happening out there somewhere, just because you haven't heard that it is, or read somewhere that it is, doesn't mean it isn't happening.