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The vehicles listed by you are all optimized for low octane gasoline; they will run on ethanol, but suffer a fuel economy penalty without a real corresponding power benefit. An engine designed to run on 87 octane will have a compression ratio of, maybe, 9:1. An engine designed for alcohol can power a 15:1 compression ratio. An engine designed for alcohol needs a less complex cooling system, benefits from a longer intake venturi, responds more effectively to supercharging, etc. The trouble is, while a car designed for 87 octane will run on ethanol, just at a penalty, a car designed for ethanol won't run worth a hoot on gasoline.

My current truck is a 2006 Silverado. While I fill it almost exclusively with e85, it gets better mileage on gasoline. GM could retune the engine for alcohol, but it would then require a very high octane gasoline where ethanol wasn't available (and it still wouldn't run as well on it). There just isn't that sort of demand yet.

I used to have a 1972 Nova which we modified to run denatured alcohol (in the days before electronic ignition and fuel injection). That sucker wouldn't run at all on unleaded gasoline, but it was a rocket on ethanol.