Below is an excerpt from the book "1,001 Things They Won't Tell You," which was published in May 2009 and highlights popular columns from SmartMoney's long-running "10 Things" feature.
Stations earn on average between 10 and 15 cents on a gallon of gas. Ironically, they earn the least when prices are highest. When fuel climbs, gas stations must shrink their profit margin to remain competitive, meaning they earn less per gallon than usual. But another big cost during tough times is something they can’t do anything about—credit card fees, which add up to about 2.5 percent of all purchases. When gas is at, say, $2 a gallon, the station pays credit card companies 5 cents a gallon; when gas hits $3, that fee becomes 7.5 cents—more than half the station’s entire average profit. “Those credit card fees are miserable for the gas station business,” says Mohsen Arabshahi, who owns five Southern California gas stations.
How do station owners make up for lost revenue? “Prices go up like a rocket and come down like a feather,” says Richard Gilbert, a professor of economics at UC Berkeley. For several weeks after wholesale prices drop, stations can earn as much as 20 cents a gallon before retail prices are lowered to reflect the change.