You're confusing E10 with E85.
E10 is commonplace all over California.
It's a 90% gasoline / 10% ethanol mix; every since MTBE was found to be a major pollutant, ethanol has been used in it's place to oxygenate our fuel and cut down on NoX emissions.
Don't get excited...E10 is not a miracle fuel by any measure. Ethanol contains less energy by volume than gasoline; because of E10's reduced energy, our gas mileage is about 5% lower than on straight gasoline.
What you're thinking of is E85.
That's an 85% ethanol mix. In that case, you're absolutely right.
The GM FlexFuel cars have various sensors and different ECU tunes to adjust the fuel injectors to match the ratio of gasoline and ethanol being used.
Obviously, the Integra lacks these sensors and ECU tuning.
It cannot run E85 from the factory.
If you try to run E85 on a car that is tuned for E10 or pure gasoline, permanent engine damage can result. On a gasoline tune, the ECU won't deliver enough E85 to run safely. The car will run lean and detonation will cause serious engine damage.