Ethanol was developed as an extender. It was viewed as a real threat by the oil industry, till they got a piece of the action.
The best companies (of which my former company used to be one till they went chasing solar) used ethanol as a way to make cattle feed and CO2. That makes you a decent amount of money, and keeps your by products balanced.
What happened recently is that corn got so cheap the beef producers would rather feed high carb diets to the cows (corn alone is not good for them) than the normal ration. Many have scaled down. Also, the wet mills are not making as much sugar lately because we don’t drink as much soda as ten years ago.
I remember filling my truck with the new "regahol", regular leaded gas with 10% ethanol, in the late 1970s for my long commute to school. This was not long after the oil embargo, back when Jimmy was still President Carter and brother Billy was still selling his Billy Beer and marking territory.
The only reason people said to use it, regahol, not Billy Beer, was that it might help keep the gas line from freezing in the nasty cold Iowa winters.
I think that was even before the Polar Vortex, too, back when we were told we were headed for the next ice age, before they invented Global Warming, so I'm feeling old all of a sudden.
It was "new" at the time. I think it might have been a bit cheaper, too, just to get people to buy it.
Now? Try to find a station with pure gas. I'm lucky to live close two stations, only a mile away from me, but I lucked out moving here.