It sounds like some "transitional learning" is already taking place. In RV's, when dry camping (or relying on internal water supply and black/gray tank capacity) things like leaving the water running while brushing your teeth, showering without turning the shower head off while soaping, leaving the water running while washing dishes and other "wasteful practices" will hasten emptying the FW tank and filling the WW (waste water) tanks....
We all "learn the hard way" how to conserve water, maximize holding tank capacity and "avoid the agony" of being in the shower then the gray tank is full.
With practice, you'll learn how to make 45 gallons of fresh water last a week and how to "fit that 45 gallons into a 38 gallon waste tank".... Seems impossible, especially to new campers, but in no time, it'll all be "part of the joy" of dry camping...... Trust me on that