....
We practice much of that and our area, when it has officially been in drought for months, is still largely green and lush, if not nearly where it is right now, with sufficient water that there is a puddle in my basement.
Lawns are a modern abomination which I suspect were pushed on us by the companies wishing to sell us their mowers, though I have not done the research on the history of lawns (yet).
The places that require lawns are bizarre.
The places that regulate cisterns and water barrels... that's a different issue.
I am not indulging in drought boasting, but will say that drought probably means something different in eastern Mass than here. (who knows, we may someday have transcontinental water pipelines, though the energy involved in pumping would be crazy...)
Yes, regulating cisterns has its issues - makes some sense to regulate and inspect where people might not properly set up the system to keep the water safe, clean, mosquito larvae free, etc.
As my wife points out, as simple a measure as gravel instead of paving makes a difference in how the land retains rain water.