I am the OP. This one has really taken off.
I never bothered to call the Pilot back because in hindsight, based on comments by others in the thread, I realized it would be a fruitless waste of time.
My reason for posting was that one really needs to be vigilant at this full serve facility and don't assume your selection will be honored.
WRT premium fuel, there is little doubt in my mind that petroleum manufacturer's make a larger profit selling "Premium" when compared to "Regular". If this were not true, the manufacturer's would not be attempting to convince me via advertising to select Premium.
I have no proof of this, but I suspect that the fuel attendants receive some sort of bonus at the end of the day for up-selling Premium. Up-selling was a common practice in the service industry where I worked while in college, pizza delivery. Suggest selling of extra cheese and cokes was expected: "Would you like extra cheese or cokes with that?".
In closing, I don't think it was a simple mistake/oversight. Let the buyer beware...