Panicked consumers fueled a 12.3 percent spike in comparable sales at the retail giant for the five weeks ended April 5 as shoppers loaded up food, paper products and cleaning supplies, the company reported. 

But the long lines and full shopping carts were deceiving. Wall Street had counted on a 24.1 percent comp-sales increase based on how many shoppers were flocking to the stores. Costco’s sales began to soften in mid-March when government restrictions addressing social distancing and non-essential merchandise kicked in, the company said. 

Management blamed the slowdown on those restrictions — which reduced store hours, limited the number of shoppers that were allowed into the stores at one time and closed non-essential departments like jewelry, optical, hearing-aids and food courts. 

Customer traffic at US stores was up 5.3 percent and the media attention Costco has gained during the pandemic likely “helped the company on the membership front — a phenomenon that we’ve seen in the past,” wrote Gordon Haskett analyst Chuck Grom in a research note. 

Costco’s shares were down nearly 2 percent, to $300, in mid-morning trading on Thursday.