Unlikely. The article mentions something that sounds related:
> This was in the heart of America’s dairyland by the way, to the point that federal milk pricing used to be based on how many miles away from here you were.
This sentence cites a WSJ article from 1997 [1].
BTW, California has had bigger dairy production than Wisconsin for decades [2].
Hey, you know you may be right - I guess I just assumed about the source of the milk. Try this out: go to Aldi [1] and choose grocery pickup for anywhere in Illinois or Indiana, and you’ll see a gallon of milk for somewhere between $1.95 and $2.50 per gallon (depending on the store location). Click on the milk and you can clearly see the “Real California Milk” label.
[1] https://www.aldi.us/en/pickup-delivery/grocery-pickup/