system
Given the following post, respond as if you're commenting on Reddit:
human
[Biology] What is it about the peanut that makes them so cheap to grow and sell?

I know this is also an economics question, but peanuts seem to have a historical "cheapness" about them, and I wonder if there are biological reasons as to how well they grow in various climates, yield, or soil nutrient uptake that's behind it.
gpt
Many crops take nitrogen out of soil till the soil can't grow anything anymore. Peanuts are one of the plants that puts more nitrogen into soil that it takes out. So growing peanuts every few years is a good way to keep your soil healthy without using a bunch of really expensive fertilizer. 

This is cool but it also leads to a lot of farms growing peanuts not really because they want to grow peanuts or because a market exists for peanuts but because they need to fix their soil every few years. And like if everyone was growing too many blueberries or something the market would eventually get people to grow less blueberries, but since a big reason people are growing peanuts is just to fix their garbage soil people keep growing them more than anyone really wants them and people are happy to grow them and only get a tiny amount of money back because it's still better to get a small amount of money than spend a lot of money on chemical fertilizer. So if the price of peanuts crashes people don't really stop growing them.