[sammyg2]

With the exception of those blended with ethanol (shudder), gas is gas so long as it has the same octane rating. Its all the same, prolly came out of the same tank. If not, it will come from a different place next week than it came from this week. Also it is dependent on the refining process that varies within tight limits, but does not always produce the same thing. It varies and the lab chemists blend it to obtain an exact product that meets specifications and is farily tightly controlled. Chances are it is sold to a wholesaler who supplies many different brands.

The ONLY difference is the additive packages, and they aren't all that different. Buy the cheap gas, put in a few capfuls of techron, and you have Chevron gas.
It really is that simple.
I've worked in many different refineries over the past quarter decade, none of em have any special process or secrets that make better gas. trust me on this one.