Following the Clean Air Acts in the US in the 90's, the plastics industries were willing to purchase certain portions of petroleum, and fuels, both gasoline and diesel, have been continually depleated ever since.
Because those acts gave manufacturers specifics on the formulations of what fuel was going to be like, a couple things happened. First, the base is the same more or less. Next, there's a lot of what one would call "coopertition" where fuels are used where they can be used. Yes, BP might be making something here, but Citgo might be low, so everyone replentishes each other to keep the market moving forward selling fuel every day everywhere.
The additive packages make up a very small portion of the actual fuel.
No, I don't have any links to back it up as this was what we learned racing through the Clean Air Acts of the late 80's and the 90's. Eventually, no street gas really is very different from another.
Flame away...
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