If you are disposing of the corn anyway, why not turn it into Ethanol and then burn it as car fuel?
The only real issue with Ethanol IMO is that corn Ethanol is preventing progress in advanced synthesis made out of, ex: switchgrass cellulose. There are better sources of ethanol if we invest into them.
The carbon footprint thing doesn't past review of the overall literature. There's one outspoken guy who has to bend over backwards and publishes media articles rather than keeping things academic who tries to make the public believe what you say, but I'm not convinced he's arguing in any serious manner.