Christopher Mims:

With brick-and-mortar stores closing at a record pace, retail in the U.S. feels like it’s at a tipping point. Many of the stores that once filled the malls of America have become “zombies,” while online retailers capture ever more of the most valuable consumers—the young and affluent.

Legacy retailers are trying to play catch-up, but they’re saddled by huge fixed costs, investors who prefer dividends to innovations, and CEOs incentivized to focus on the next quarter, not the next decade. It’s only a matter of time before Amazon.com ’s AMZN -0.75% army of physical retail formats turn into an existential threat to everyone from mom and pop to Kroger and Wal-Mart . WMT -0.10%

That doesn’t mean retailers are taking this lying down. As online brands begin to build physical shops, the old guard is taking notes—and in many cases, writing checks. Wal-Mart, for example, has been on an acquisition binge of late. It’s now in talks to buy men’s clothier Bonobos for $300 million.