(Is it gauche to quote myself?)
Drove past that same Sam's Club about 11:00am today. Prices rose to a posted $2.79 - up 9˘ per gallon in the last 2 days! Gloria stopped there about 6:00pm tonight and filed up at $2.76 before the 5˘ Sam's member discount, down 3˘ within 7 hours. Seems there is no rhyme or reason in pricing gasoline.