TenOC...I have no problem getting the $.05 per gallon discount on gas. Have gotten it at many Pilot/Flying J gas stations. At the pump, I scan my Good Sam membership card (first, if I recall correctly), then I scan my credit card (no need for a special Flying J credit/charge card), then the pump prices change to $.05 lower, then I pump my gas.
I see at the bottom of the website mentioned above, in fine print is:
"Discount available at company owned and operated Pilot Flying J locations."
Maybe there are non-company owned stations where you have tried to get the discount??