A rose is a rose argument....so they hid the ethonol subsidy in the Renewable Fuel Standard requiring so much of the fuel be composed of mostly corn. You are right, there is no ethonol per se subsidy.
The Renewable Fuel Standard should be repealed (as should all other laws mandating American citizens to engage in, or not engage in, any activity against their will).
Excellent: Senate introduces a bill to abolish RFS biofuels mandate
It's a START!