It's an extremely important point when you consider the water going to things like almonds in California, the majority of which are then exported. Their almond crop alone consumes enough water to supply Los Angeles and San Francisco combined. Only 20% of California water is for non-agricultural purposes.

Or put another way, the total economic value of all exported almonds from California is about $3.5 to $4 billion. The water use is about on par with the entire city of Los Angeles for that almond export crop. The metro area of LA has a trillion dollar economy by comparison (250+ fold larger than the almond exports). That's an economically irrational imbalance.

The obvious question becomes: is that what California wants to do with its scarce water resources, export large parts of it at an extremely low value basis? At some point in the near future it's likely some hard choices will need to be made, including whether to invest extremely large sums of money into more desalination plants or to begin restricting the most voracious water consumers (cattle are another one, although I'm unsure of their export ratios).