That is why we started producing corn-based ethanol. It wasn't intended to see people grow corn for it, but rather clean up the unmanageable excesses realized in the due course of growing it for food-based reasons that otherwise would have been left out to rot. In that vein, J is insignificant as it is spent either way.
The problem is that humans aren't very good at moderation. A little ethanol production is quite sensible, but once humans get it into their head something might be sensible in small doses they have to take it to a ridiculous extreme... You see that in everything.
As a corn grower myself, I wouldn't go that far. Ethanol production is really only profitable when corn isn't profitable to grow. In other words, when you have ethanol plants champing at the bit to buy your corn, you are wishing you hadn't grown it in the first place! It can be a profitable crop, but only on the backs of food buyers who are much less price sensitive.
Ethanol does serve as a helpful buffer to step in when corn would be otherwise worthless, where the alternative is to let you see it rot, minimizing the losses — But if you are counting on ethanol to make you rich... Good luck!
Granted, there was that strange period around the early 2010s, in reaction to the early-to-mid 2000s where corn was being left to rot, where the US government was paying ethanol producers to produce ethanol. If you are posting from a time machine from that time, I get what you are saying. But those days are long behind us now.