It differed by city/province. In Wuhan and other major cities in Hubei things were more challenging. But in Beijing and Shanghai, grocery stores remained stocked and food delivery companies kept running. Here’s a video from an American in Beijing. In HK there was a run on rice, toilet paper, cleaning supplies (bleach, anti bacterial wipes, dettol hand soap), masks etc. Whether or not there is a run on food or other supplies has more to do with fear and panic than the actual virus itself. Panic spreads faster and is more scary. You are better off being fully prepared early. Most of the stuff you buy is for any emergency and will last.