My uncle has been a farmer for quite a while and his children took on the farm after he "retired" (you never really retire when you're a farmer). I've worked with them and I've never seen them water the crops. They don't even own the tools to do so and yet they're growing cereals (and a hundred cows) on 300 acres. They live in the east of France where I've never seen crops being watered. Not to say that you're wrong but I can't confirm your statement given my experience with farmers.