My dad uses 100% gas religiously in anything with a carburetor. On his outboard, he unplugs the fuel line from the motor, while its on the trailer, on the ramp, but still in the water, to let the remaining gas in the motor burn up. His outboard is a '76 E-rude and still starts with no more than 3 pulls. I don't believe he has ever even had the cowling off that motor.
I used to not care about ethanol, but got sick of cleaning carbs every spring in my lawnmower. I recently purchased a new mower and will only be using 100% gas and will be emptying the tank every winter.