Wow this is insane. The culture I grew up in is famously health-friendly, so I've never come across this, but it sounds horrible.
I started drinking only water around high school, and the only reaction I ever got was "good for you, I wish I had that habit".
> Because something like this still costs money, it helps convince the purchaser that they aren't appearing to be "cheap" by only ordering water.
Interesting, you think that appearing cheap is behind the stigma? I would've guessed it would be something along the lines of anticipated reproach.