The pandemic got seniors to buy groceries online. That might not last.

The virus was spreading fast, and Brookdale's residents were being encouraged to stay put. Staff set up computers in the main common room and began teaching residents how to open online accounts to order groceries.

Crowell's first attempt to order from Kroger Co.'s Harris Teeter chain failed, so the 85-year-old retiree switched to another local grocer's website only to discover an annoyance familiar to legions of online grocery shoppers: substitutions of her favorite brands and products. "Once, I ordered a few ounces of bouillon and got a great big quart bottle," she said. "It's still in my closet."

Crowell tried Harris Teeter again and succeeded, ordering seven times between May and August. But when the holidays rolled around last year, Crowell was once again walking the aisles. "There's just something about picking up your own stalk of celery," she said.

The covid-19 outbreak super-charged online grocery shopping, prompting industry watchers to declare that the habits of millions had forever changed. In fact, it's a little more complicated than that. Yes, Walmart, Kroger and other chains picked up millions of new online customers-generating additional revenue and persuading even skeptical executives to expand their digital operations. But holding onto these shoppers is hardly a foregone conclusion-especially older ones like Crowell, who are already reverting to pre-pandemic behavior.

That's bad news for web grocery specialists like Instacart Inc., which processes orders and deliveries for thousands of supermarkets and has helped almost 300,000 senior customers figure out how to use its service. It's also not great for brick-and-mortar food retailers because shoppers spend considerably more when they buy groceries online than when they have to lug everything home themselves. And there are more seniors online than you'd think: More than three in 10 people age 60 or older shopped for groceries online in April, according to consultants Brick Meets Click and Mercatus, and the number of seniors using Instacart last year rose faster than any other age group.

Almost half of Baby Boomers surveyed by Morgan Stanley said they'll continue to grocery shop online at the same rate they did during the outbreak. Those seniors who stay online will do so because e-commerce has "become ritualized as a part of everyday life," says Columbia Business School lecturer Robert Morais. It's what anthropologists like Morais call an "adaptive strategy," not unlike when humans went from foraging for food to agriculture and then onto large-scale manufacturing.

But the number of seniors using web grocery regularly declined by 25% in April compared with the previous year, Brick Meets Click and Mercatus found, the biggest drop of any age group by far. That suggests many seniors are still hunter-gatherers at heart, Morais says, and often prefer to use their senses to choose the food that's most appealing, like Crowell's celery. Jody Holtzman, an expert on the so-called longevity economy and the former head of market innovation at the AARP, says seniors will probably split their shopping going forward, using the web periodically to stock up on staples like canned goods and cereal and reserving in-store trips for produce, fish and meat.

There's also the social aspect of shopping and interacting with staff and neighbors, something that's particularly appealing for older Americans who were unable to see friends and family during lockdowns. Vivian Paquette, 85, another resident of the Brookdale community who started online shopping last year but has since given it up, says she enjoys chatting with the cashiers at the local Harris Teeter.

"I feel I have a connection to the store," she says. "This might be the only person I talk to today!"

Grocers are responding to the defections by offering more enticements to stay online. Kroger doled out half a trillion personalized product recommendations to its digital customers last year. Albertsons, which operates 2,277 supermarkets under banners like Safeway and Vons, is doing online cooking demonstrations. Instacart created a "Senior Support Service" last fall to help older customers get accustomed to ordering online and says it's growing by about 1,000 users a day this year. Other chains will waive delivery fees if shoppers come back online or offer discounts.

"As the necessity imposed by the pandemic lessens," Holtzman says, "retailers will have to start to play the price game."

Still, all those sweeteners won't convince Paquette to hop online again. What would? "I don't know," she says. "Maybe a free lobster dinner?"