The difference is that local and state governments, the people should show up with pitch forks and torches and demand free choice of motor fuel. Those that have no problem with ethanol can buy it, and those that have serious issues with it can buy non ethanol gas. The feds only demand that a certain amount of ethanol be used, they do not state it has to be the only fuel available. And the government, local, state, or Federal, is NOT REQUIRING YOU TO USE A MOTOR FUEL THAT IS NOT RECOMMENDED FOR YOUR CAR. I have seen the E15 pumps and they are very clearly labeled that it should not be used in certain vehicles, and is illegal to dispense into vehicles not designed for its use.
Sure, ethanol fuel is less mpg and the government gets more in fuel taxes on a volume basis, but I could really care less. When the price of E85 compared to gas has a good spread, as it does now in my area, even with the decreased mpg, the cost per mile is still lower than using regular gas. Right now, based on the mpg of each fuel and the price spread, E85 costs about 3-4 cents a mile LESS to use than gas. It is about a wash between regular E0 and E10/E15. I have run the mpg numbers on all the various fuels in my vehicles. I might get a little better mpg on E0, but the cost per mile of E10/E15 is, even with a lower mpg, is equal or lower than using E0.
It is all about money again. Whatever delivers the lowest cost per mile for me to use, I use. The beauty of having a flex fuel motor. I don't stress over the politics behind it.