Concerns about the potability of water are legitimate -- but as noted, water is local, as well. If you're in a shortage area, get your water from a limited flow well, or (heaven forbid) have to use untreated surface water for your processing, conserving water means a lot more to you locally than it does if you're on a municipal water supply that draws from a river, treats the water, then treats the sewage and sends it back to the same river.
For myself, I'm on a deep well with water that's clean enough my partner used to use it straight from the tap for a reef aquarium (started filtering a couple years ago due to concerns about iron content). My septic system doesn't replenish the aquifer that supplies my water; that water is decades or centuries old, originally rain water from a considerable distance away, now filtered through limestone for many miles. As long as the electricity stays on and the neighbors don't start pumping waste down their own wells, my water will be fine -- which, sadly, says nothing about the global shortage of potable water, because there's no practical way to make a small percentage of my water available for an African village that otherwise must drink (untreated) water carried from a river.
For myself, I'm on a deep well with water that's clean enough my partner used to use it straight from the tap for a reef aquarium (started filtering a couple years ago due to concerns about iron content). My septic system doesn't replenish the aquifer that supplies my water; that water is decades or centuries old, originally rain water from a considerable distance away, now filtered through limestone for many miles. As long as the electricity stays on and the neighbors don't start pumping waste down their own wells, my water will be fine -- which, sadly, says nothing about the global shortage of potable water, because there's no practical way to make a small percentage of my water available for an African village that otherwise must drink (untreated) water carried from a river.

