Ethanol only releases 50-75% the useful energy per Litre than petrol (9:1 Stochiometric iirc). Does have a great octane boosting (knock reducing) effect though.
Maybe its for a classic carb'd car or in higher elevations? Running Ethanol effectively leans out the mixture - not good for a car which is at high altitude (less air) and/or with no ECU to control things dynamically.