No, agriculture has fairly strict standards about the quality of the water, they can't use gray water to irrigate. Of course it will still work but depending on where you live the produce may then no longer be fit for human consumption.

You can use it for irrigating your lawn but not for vegetables, especially not if you plan on selling them. But 'light' gray water requires relatively little treatment before you can use it again, however this could still be quite expensive compared to just letting it go. I wonder if they've done any quantitative research on this that's public.