$4-plus U.S. gasoline helped drive first-time fill-ups at Costco, but shares slid nearly 4% Friday as analysts doubted the retailer can keep those gains when fuel prices ease.
747 Costco gas stations undercut local rivals by about 30 cents a gallon, pulling in record demand and lifting warehouse foot traffic about 5% because roughly half of gas customers also shop inside.
Gasoline still squeezes profitability: Costco makes only a few cents per gallon, and gas cut last quarter's gross margin by 0.2 percentage point after adding about 0.1 point when prices were lower last year.
Executives said cheap fuel, $4.99 rotisserie chickens and extended meat-and-egg discounts are building loyalty, but investors focused on whether that momentum can outlast the current price spike.