Earlier quoted context omitted.
That doesn't always work as is the case for farm work once you make immigration harder. How many Americans if given a choice would rather make $40K a year doing nice and comfortable office work than make $120K a year (yes I'm making up a number to make a point) to do back breaking manual labor in the hot sun? Not quite to that extreme, but I'm giving up money now by choosing not to go into management and stay a senio…
Why is 120k the right number? Have you taken some implicit biases of your own, and decided that's the worth of farm work? The correct price of farm labor is whatever it costs to obtain it. There is no cap. It's whatever it costs to persuade people to move from their comfy office to the farm.
If someone can choose to make $30K a year and adjust thier lifestyle accordingly instead of making $90K a year doing a job that they don't want to do, many people will choose the former.
I would go so far as to say the vast majority of public school teachers make the choice between less pay and being able to do a job that they enjoy as opposed to doing a job that they don't enjoy.
Anecdotally, every person I know that decided to work in the school system (including my mom and my wife) chose to do it because of stability, being off for the summer, and being able to work with kids when they both could have made more money doing something else. I doubt you could offer them 10x the amount of money to be willing to work in the fields.
But more to the point of the article, many people would not take the trade off of the dangers and long hours away from thier families, for any amount of money.