High corn prices dont have that much to do with high food prices. Most of the edible form of the corn (what doesnt go out the back of a fat holstein) is what is a by product of the distilation process. If you've ever spent any time around a holstein, you'd see how much corn goes throgh undigested. The distillers grain (byproduct) is much more digestible and is mixed with less a filler so to say.
So instead of pushing $5 of corn into one end and having $1.50 come out, you put $5 corn into a ethanol plant, get $6 of ethanol from same amount of corn, then send dry distillers grain to farmer, and put $2.50 equivilent of corn into steer, and get 10 cents out the other end of the steer in the undigested form. There is less waste and you loose very little nutrients out of the ethanol process compared to feeding the corn directly to the steer.
And a larger precentage of corn is fed to livestock than turned into cornflakes.
And crop prices being higher means that farmers can turn a little bit more profit, and buy more modern machinery, which is more Eco-friendly. Which makes the people that work at John Deere and CNH work more, which creates a larger demand for steel, and makes the workers at the plant make a bit more, and so down the line.
Either way, sombody makes money off it, and some people loose money. Its going to happen that way regardless of E15 or none.
Personally this "Ethanol is Evil" because it directly raises food prices is really not true. In the end, more of the corn is used in Ethanol then if it goes only into livestock.