That's wrong right on so many levels - but it happens.So we pay tax on tax.
E-10 means roughly 90% Gasoline and 10% Ethanol.
E-85 means roughly 15% Gasoline and 85% Ethanol
https://en.wikipedia.org/wiki/E85
For fuel consumption, Methanol (not Ethanol – for not sure specs on it but suspect it to be about the same) needs 2.2 units per every unit of Gasoline. That means an engine will need 2.2 times the amount of Methanol as a Gasoline engine will use; therefore, carburetor jetting will need to be different (changed).
Using Ethanol or Methanol in a non-computer-controlled environment will equal an engine running way lean (or even with computers used in FMJ vehicles will still run way lean).
If a person is using an aftermarket fuel injection system, then you can have at it, providing your fuel lines and hoses are rated for alcohol usage.
BudW