I recently left a 30 year job as a gasoline transporter. Some might be surprised to learn who sells what gas to whom at the loading racks. We used to lift brand A at brand B's terminal, all the way through brands L, M, N, O, P, 7 days a week. In the petroleum business, these product swaps are known as "throughput arrangements." (The gas guys can't say things simply, like "swapping product" and so use fancy terms like throughput arrangements.)
There are exceptions to this practice, where for instance brands P, Q, and R will only sell their own products at their gas stations.
Octane rating only indicates a fuel's ability to resist knock. It really has nothing to do with level of quality. High octane fuel won't make a vehicle designed to run on 87 octane run any better or faster. Even the fuel guys will admit to that.
A dollop of trivia - by definition, there is no octane rating higher than 100.
Another thought to ponder - when product is moved up the pipelines, there is no device to seperate the products in the pipe. 12 miles of gasoline will have 10 miles of home heating oil on it's tail. Where the two products meet there is a predictable amount of co-mingled product.
Guess where that co-mingle goes? Let's just say, dilution is the solution.
