fwiw – Costco gas isn’t always the cheapest… They do super high volume – so when prices are going up – they can have higher prices than the lower volume station that filled it’s underground tanks at a lower price. When prices are going down, they tend to have lower prices than their lower volume neighbors.
But if you have a 14 gallon tank – 2cents/gallon difference is only 28 cents. Not worth driving around (or waiting in line.)