We had a station that sold pure gasoline a few years back. Doing comparisons, I got 15% better mileage over 10%-ethanol blend. Problem was, it cost 15% more and they went out of business. There is another station around that sells it but it’s 20 miles out of my way.
I’ve had THREE new cars/trucks from two different manufacturers. They all got O2 sensor failures DIRECTLY attributed to ethanol in the gas. I had to buy a CAN/OBD II tool to reset the crap engine alert. All O2 sensor damage from ethanol.