The world needs grain.   The usage is constantly increasing.  Wasting a growing season would be completely counter to the interests of society.   It would also be counter to the economic interests of the individual farmer. 

If I planted for an 80 bu corn crop, the price I would get would be exactly the same as if I planted a 150 bu corn crop.  The market does not care how much I produce...it's a drop in the bucket.  

Everyone in any business who sells anything accepts the price the market offers.   If I call for a quote on trucking, if you quote it too high, I don't hire you, I hire someone else.  If I call for a quote on an engine for a pickup, if you quote it too high, I don't buy from you, I buy from someone who will do it cheaper..  If I call for a quote on fertilizer, if you quote it too high, I don't buy it from you, I buy from your competition, or I go up the supply chain and handle it myself.  If you call looking for a job, and tell me you want to make twice what I am willing to pay, I don't hire you.  Everyone except the government is subject to market forces....