An image generated by artificial intelligence

At 2 a.m., Kim, a 25-year-old office worker, opens a site designed to look like a food delivery app, though he has no plan to order. He chooses menu items, drops them into a cart and simulates the experience of placing an order.

"It somehow feels like I actually ordered something," he said.

Kim said the habit helps him resist late-night cravings.

“There are many times when I crave food late at night but hold back to save money. It feels like a real delivery app, so I somehow keep looking at it,” Kim said, referring to a site whose name is a spoof of a food delivery app.