Orlando Chase, standing, and John Sullivan, a.k.a. “the whale man,” panhandle at their usual spot in Washington, D.C. Passersby increasingly tell them they have no cash.

WASHINGTON — John Sullivan wears a giant foam hat in the shape of a whale. It works well as a conversation starter when he panhandles on the corner of Wisconsin Avenue and M Street in Georgetown. But one hot afternoon in July, no one stops to ask Sullivan about the whale. And no one stops to drop a dollar in his pink plastic cup.

Passing by, one young man in sunglasses turns and shrugs. “I don’t have any cash,” he says apologetically.

That’s a refrain Sullivan has heard a lot lately. He has panhandled in the same spot for almost 20 years and has a good rapport with the locals, who call him “the whale man.” But in the past three years or so, more and more pedestrians have been telling him that they no longer carry paper bills or loose change.

Sullivan’s good-natured about it: “I’ll see you next time,” he says with a smile if a passerby claims to have nothing but a credit card. Lots of people actually do come back the next day with change, he says — but still, he takes in only half what he once did.

Orlando Chase, who panhandles on the same corner as Sullivan, isn’t quite as patient as his friend. “They say they got credit cards,” he scoffs. “I gotta eat. I can’t eat with their credit cards. That’s a done deal.”

A decade ago, you probably wouldn’t have thought to go out without at least a crumpled $5 or $10 bill in your pocket. Nowadays, though, you can use credit cards just about anywhere — and a growing number of smartphone apps are letting us swap clumsy cash for simple swipes when paying a cabdriver, tipping a delivery guy or even splitting a tab with a friend.

It’s all very efficient. But for panhandlers and street vendors, all that efficiency just translates into a whole lot less generosity.

Within the next five to 10 years, the United States could become a “less-cash” or “cash-light” society. That’s the prediction of Harvard economist Kenneth S. Rogoff, who envisions a day when physical currency will be phased out of most legal transactions. A recent survey by Ipsos found that 38 percent of U.S. respondents would ditch cash completely if they could, while 34 percent report that they already rarely carry it.

For panhandlers, who rely entirely on the real stuff, that means less income, period. In Franklin Square in downtown D.C., Carrie Evans hits up passersby for a little change. She gets meals at a women’s shelter, but panhandling brings in the money she might need for a bus fare, or a bottle of water. “A lot of people say they don’t have cash,” she says. “Everybody carries plastic.”

Back in Georgetown, at the corner of 27th and K streets, Nathaniel Bost gets the same song and dance. “They say, ‘I got a card,’ ” Bost says. “I say I need cash. They say, ‘Can’t do it.’ “

In his book “The Curse of Cash,” Rogoff suggests that a cashless society could provide heavily subsidized debit-card accounts and perhaps smartphones to low-income individuals. He notes that in Sweden, where less than a fifth of transactions are conducted with cash, some panhandlers already accept donations via mobile phones.

But it’s hard to imagine some veterans of Washington’s streets adjusting to such a system, which would require a bank account and a Square credit-card processor, not to mention time, internet access and technological savvy. Chase is 60 years old and has panhandled with a plastic cup for years: He had never heard of Square.

As for Sullivan, the “whale man” wouldn’t deploy his smartphone in the course of panhandling. “If you got a phone, people think, how can a homeless person have that?” he says. “They think differently of you.”

In 2003, James Davis was staying at the Central Union Mission shelter when he heard about plans to start a newspaper written and sold by the homeless. He became one of the first staff members of Street Sense, a biweekly newspaper about homelessness and other social issues. The paper’s vendors — most of whom are homeless — distribute it on the street for a suggested donation of $2.

Davis is no longer homeless, thanks in part to the money he earned writing for and selling Street Sense, and he now trains other vendors.

In recent years, many have complained that they’re just not bringing in any money. “The new vendors get discouraged because people don’t stop anymore,” Davis says. “I say, it’s just because they don’t have cash. I know because I’ve got three kids.” They’re all millennials, he says, and none carry change.

“People would just put their hands up in the air and say, ‘No cash,'” says Robert Warren, a part-time vendor who has lately struggled to earn as little as $30 in a seven-hour shift. Warren has mostly quit vending because he was earning so little.

Street Sense editor Eric Falquero brought up the issue at a conference for the International Network of Street Papers last year. He found that street-paper vendors worldwide had experienced a drop in sales, and some had started accepting electronic payments.

Street Sense has worked with software developer Denim & Steel to build an app to let customers purchase the paper digitally. When it launches, a customer who meets a vendor on the street can select that vendor’s profile and transfer a direct donation electronically. Vendors themselves need not have smartphones.

In Seattle, entrepreneur Jonathan Kumar has developed an app called “Samaritan,” which equips homeless individuals with Bluetooth-enabled “beacons.” When someone passes a “beacon holder,” they can donate via the app. Beacon holders can then use the funds to purchase goods from participating local merchants.

Both apps are interesting solutions to the problem posed by looming cashlessness, but they’re designed to help panhandlers and street vendors already connected to charitable organizations. (Kumar works with local nonprofit organizations to identify homeless individuals who might benefit from the app). But the ones who panhandle are often those who are least likely to connect to established programs, according to Brendan O’Flaherty, a Columbia University economist who has studied panhandling and homelessness. Some have mental health or substance abuse problems that make it difficult for them to follow through with resource providers; others enjoy the freedom of living on the streets and distrust those providers.

Why keep panhandling, when it’s less lucrative these days?

Sullivan plies his trade just a few blocks from the Georgetown Ministry Center’s shelter. He knows the staff, and he’ll accept a bottle of Gatorade from the shelter director, but never his offer of a place to sleep. He prefers to set his own schedule and earn his own money: It’s what he’s done for decades, and he’s not going to stop now.

Even as panhandling becomes harder, he finds a certain joy in it. “People don’t owe you nothing,” he says. “It’s all about the love.” His regulars, at least, still usually have change for him — or if they don’t, they might buy him a sandwich.

“For some people, it’s a social outlet,” says Columbia’s O’Flaherty. “They have regular customers, relationships that develop all the time.”

That could all change with the technologies that enable digital transactions, because they don’t just eliminate the need to carry cash. They also reduce the social interactions that come with the exchange of money. Order an Uber, and there’s no need to give your driver directions. Split a check down to the penny with Venmo, and there’s no reason to debate who ordered what at dinner. Carry nothing but a credit card in your wallet, and you have an excuse not to stop for the panhandler trying to flag you down.

On the other hand, says O’Flaherty, technology could end up leaving us craving face-time with familiar folks. So while some may be less willing to stop when a stranger calls out for spare change, they may be more willing to chat with the man they see on the street corner every day.

With any luck, panhandlers’ regulars, in other words, will stay regulars, Venmo or not.

That’s proved true in the vendor world, or at least for some of Davis’ customers. Josh Weinberg, who sees Davis every weekday when he leaves the National Geographic office, has several dollar bills in his wallet. He exchanges two for a copy of Street Sense.

“For things like this,” he says with a shrug, “I like using paper.”

James Davis, right, hawks Street Sense, a newspaper produced by homeless, at a Washington, D.C., street corner. Davis says that new vendors find it difficult to earn much selling the paper because fewer passersby carry cash.Though he collects less money these days, John Sullivan still finds a certain joy in panhandling. “It’s all about the love” he gets from his regulars, he says.

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