Unless it has changed , there is a large fuel distributor in Paducah and when a tanker fills up , they use a "credit card" to swipe and get the additives mixed in when the fuel is filling the tanker. Shell , BP . Exxon , etc. comes from the same terminal . These cheap gas pumps at convenience stores have ZERO additives to their fuels. This is where mileage becomes a factor. AFA , water in the tanks , truckers delivering the fuel should be sticking the tanks before and after w/this paste applied to the end of a long wooden stick to check for water .
There E85 fuel pumps over in Mo. and they sell a lot of fuel. Whew , talk about poor MPG !