• Shoe chain’s weak earnings drag down other athletic brands
  • Results contrast with generally strong Christmas season

After the strongest holiday-shopping season in more than a decade, investors have grown increasingly impatient with retailers that didn’t enjoy the good fortune.

Shares of J.C. Penney Co. and Foot Locker Inc. tumbled on Friday in the wake of lukewarm results during the fourth quarter, which included the crucial Christmas season. The chains both posted weaker-than-expected comparable sales, a key benchmark.

The sharp reaction underscores the concerns that are still swirling around brick-and-mortar chains in the U.S., even as the retail picture brightened in recent months. Foot traffic remains sluggish at many American malls, and Amazon.com Inc. gobbled up about half of the e-commerce growth during the holidays.

The industry also is facing a tougher problem: Even after closing thousands of locations in recent years, U.S. retailers still have too many stores.

“We still think there are more store closings ahead in 2019 and beyond,” said Poonam Goyal, an analyst at Bloomberg Intelligence. “The landscape in the U.S. is still very much overstored.”

More than 100 million square feet in store closings were announced…