The free market would stipulate that if there was a shortage of farmers...then the value of being a farmer would go up significantly enough to fill in the shortage.
If pumping sewage into a honey wagon payed 100 bucks an hour....people would be kicking the doors down and getting college degrees in order to get hired into that “Career”.
And you know what...if enough people refused to pump sewage at the current labor rates...it would eventualy pay 100 an hour.
It’s not easy being a farmer and it’s really hard to start
farming unless you have a lot of money for the initial investment and if you have that kind of money you probably don’t want to farm.