Ever hear about 'closer to the source of manufacturing/availability the cheaper the product in question is?'
Oil seems to be the only product that breaks the rules. Another rule is the instant price change in the middle of a work day for gasoline. Again it's the only product that does that. I don't think a jewelry store alters prices for gold/silver products in the middle of a business day.
. . .had one of those in a truck that pulled up to the gas pump awhile back. . .usually I just ignore the barking and growls but not with that breed. . .