When it comes to MPG ratings there's a new dynamic that people rarely account for.
The EPA test is done with 100% gas. Most people reporting their real world MPG are probably running E10. Mileage is impacted when runing this fuel.
Here in Texas all regular consumer outlets are now E10 with a smattering of E15 & E85.
bingo, you're a thinker! What kills me is that the gasoline has been diluted by 10-15% where is the corresponding 10-15% reduction in price? So not only do you get a worse mileage, you pay a premium for it!