Costco has discreetly increased gas rewards for holders of its branded credit card.Members with the Costco Anywhere Visa Card, issued by Citi, can now expect to earn 5% cash back at Costco gas pumps, up from the previous 4%. The higher rewards apply only to gas stations located at the warehouse giant and do not extend to any gas purchases outside the company or electric vehicle (EV) charging.  However, all other eligible gas purchased outside of Costco and EV charging will earn 4% cash back. Both the 5% and ...