Howard,
there are two issues with ethanol.
Firstly is traps moisture in the fuel. as the water is immiscible it forms a layer or drops. When the water hits the engine the fuel dosing maybe right in volume but not in stoichiometric mix so you run lean.
Secondly the alcohol & water can attack fuel pipes , tanks, pumps etc. In my garden hedge trimmer it dissolved all the fuel lines in the tank!
You are right but the question is "how serious is the problem"?
Ethyl alcohol in fuel destroyed some plastics used in fuel lines, mainly but not wholly in garden equipment and similar. But it also damaged plastic fuel tanks on Ducati motorcycles. That issue should not affect modern cars at all, and cars that are affected have to have the fuel lines changed. But its a fit and forget situation - trying to dodge it by only buying fuel you think is alcohol free is not reliable.
The water seperation is unlikely to be an issue with a car becuase of the rate of fuel useage, with the exception being cars stored for the winter. Even on boats where everything is much damper, it isnt in my experience an issue during the season. I have had the diesel bug ( a related problem) 4 times but every time has been on a newly bought boat that has been stood doing nothing for a season.
Might be interesting to put a gallon of petrol in a vented glass jar and see how long it is before any seperation happens.
