The current wave of coronavirus cases is sure to ignite a consumer stampede to purchase toilet paper, household cleaners and other staples. Walmart CEO Doug McMillon said on a recent quarterly earnings call that new regional shortages have everything to do with local COVID cases. “We’re going to be able to respond in this instance better than we did in the first half of the year, although we’re still — as a total supply chain — stressed in some places,” he said. Many stores have set lim...