Agrichemical companies mint fortunes by selling seeds and chemicals to farmers, and grain processors reap billions from buying crops cheap and turning them into pricey stuff like livestock feed, sweetener, cooking oil, and ethanol. But the great bulk of US farms are run by independent operators.
Biofuels may contribute to, rather than reduce, greenhouse gas emissions, because they provide incentives to plow up carbon-trapping old forests.
E15 only works in cars manufactured after 2001. It doesn't work in older cars, it doesn't work in boats and devices like chain saws, utility vehicles, and lawn mowers. In fact, it can destroy those things if you use it accidentally.