Those figures are for water that doesn't enter the plants, though. All that water, except for a tiny fraction represented in the shipped output (nuts, whatever) still ends up locally in the air.

And "disappearing into the ground" is absolutely not water entering an aquifer! All you get is wet dirt. Which then... dries out. Again, this isn't how aquifers work.

There's no free lunch here. Growing plants in a desert under the open sky requires a staggering amount of water. It just does. If you want to push efficiency measures look at greenhouses.