system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: if fresh/drinkable water is so scarce, why do we use it to clean and wash our stuff? Couldn't we use something else?
gpt
There are diminishing returns at some point. Depending on the area and situation, there are  some areas that ban things like watering lawns, washing cars etc in order to reduce consumption. But there is a point where the savings incur costs too - unsanitary practices, lack of hygiene lead to disease and other health issues. The little savings by not washing leads to even more waste and loss in other areas. 

In general, day to day stuff like cleaning clothes, short showers, use for waste disposal and drinking do not consume a lot of water per person. Alternatives would be expensive, inconvenient and possibly dangerous (eg cleaning chemicals).