Even though you think gas costs a fortune—because it does—gas stations make little, if any, profit of fuel sales. Their cash cow? The cheap, pink sunglasses.
Gasoline prices hover at around $4 a gallon nationwide, but oil prices are so high that the seemingly exorbitant prices aren't enough to keep gas stations in business. According to USA Today:
They make only pennies per gallon sold. Most of the profit, about 75%, comes from the markups on convenience store items such as sunglasses, hot food or medicine, according to the Associated Food and Petroleum Dealers, or AFPD, a trade association of independent operators.
So just remember: the next time you're scooping up a four pack of powdered donuts while refueling—you're helping that gas station stay in business. Petroleum and empty calories: It's the American way. [USA Today via Slate]