Katana Scannell arrived at work at a Sam’s Club in Athens, Ga., early Friday before opening hours, and headed to the back of the store. She was greeted by a young woman walking the other way: “Good morning, Katana!” Ms. Scannell, who is 21, felt baffled, and unsure who the person was: “I was like, ‘Hi?’ ” Minutes later, it registered: it was Jaenise Jones, her co-worker. Previously, both of them always wore masks. But on that Friday morning, Ms. Jones didn’t—and Ms. Scannell hadn’t recognized her peer’s bare face. “Oh my God,” says Ms. Scannell. “It really tripped me up.”