That is me. Fortunately I can go to the corner store in such an emergency 
Indeed. Access to clean water is something too many of us take for granted, especially when you look around the world and see what water access is like for most people.
ETA: Board issues made this a double post.
I don’t know that all of those are conclusive (e.g. there’s a fair bit of controversy about whether artificial sweeteners affect insulin production, and the diabetes etc. correlation is just that, correlation != causation).
That said: I’ve found that flavored seltzers are a pretty good option. I won’t drink enough plain water, but I will drink flavored seltzer. The store brands are pretty economical but the brand names are very nice.