You don't believe that the entire agriculture industry has any effect on water losses?
Apparently pot farms are wreaking havoc on water supplies in Norcal because there is so much cultivation and water theft, wells and entire aquifers are starting to go dry in some places.
A couple crops in CA that have become more widespread recently are rice and alfalfa. I've read these take massive amounts of water as flood irrigation is common, while most of these crops are exported over to Asia rather than domestic consumption.
I wouldn't say that most Yanks don't get it, though. Some don't, but most do. The big problem here is the system of water rights where long-time senior rights holders of stream water can take as much as they want at zero cost, while less senior rights holders get nothing.
I think this system is written into the State's constitution, though even if it were not I don't think the politicians have the backbone to reform. The drought would probably be long over before all the lawsuits would be settled.