This week, I was driving in my neighborhood when I spotted that most American of sights — a bunch of kids running a lemonade stand, waving signs and trying to flag down passing cars. In some ways, it seemed like a great business opportunity — the temperatures where I live have rarely dipped below the high 90s lately. And yet I didn't stop — not because I don't like lemonade (or kids), but because I simply don't carry cash anymore, and I'm fairly sure the neighbor children weren't taking credit cards. This got me thinking about all the people and sectors of our economy that are still dependent on cash, and how they might be affected by our increasingly cashless society. More from Recode:

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Cash is in decline

Whether anecdotally or based on solid data, I think most of us have a sense that cash is in decline. One study from last year suggests that cash is the preferred payment method of just 11 percent of U.S. consumers, with 75 percent preferring cards. In other markets such as China, cash is dying out even more quickly, with mobile payments increasingly eating into both its share and that of cards. Though my local dry cleaner in New Jersey was a rare (and suspicious) exception, I very rarely come across businesses that don't take cards, to the extent that it now really takes me aback when it happens. For many of us these days, credit and debit cards — and to a lesser extent, mobile payments — are making cash largely irrelevant. I still have a huge jar of loose change I accumulated over many years, and which now mostly gets used for the occasional school lunch or visits from the tooth fairy, but not much else.

But not for everyone

However, assuming that this pattern holds for everyone would be a mistake. There are still big sectors of the economy and large groups of people that remain heavy users of cash and are heavily dependent on it, and as others move away from it, that's increasingly going to cause them problems. Sadly, this likely applies most to some of the more vulnerable and marginalized parts of our society, who will be least in a position to make the changes necessary to keep up as the rest of society moves on.

Just a few examples of people or businesses still dependent on cash: Homeless people and others who ask for money on the streets

Charity workers soliciting cash donations in public areas

Manual and casual laborers who get paid in cash, either for convenience or for tax reasons

Cab drivers

Those who don't have bank accounts or credit cards, including many without regular incomes

The elderly

The very young, also unlikely to have bank accounts

Anybody who works based on tips, from waiters and waitresses to maids and barhops in hotels to valet parkers

Small local retailers and restaurants that can't justify high credit card processing fees on mostly small purchases. The list could go on much longer than that, but the point is that there are those who are in some cases heavily dependent on cash and are relatively powerless to make the changes necessary to keep up. These are often among the poorer and least educated people in our society, and therefore those with least access to technology, the traditional banking infrastructure or information about how to adapt.

Tech has offered partial solutions

The tech industry has offered partial solutions, but mostly in self-serving ways. Payment processing company Square has transformed many a small retailer or producer from a cash-only business to one that can take credit cards and even Apple Pay, and has created ways for those without traditional cards to carry balances and make payments with their phones. Amazon has introduced methods for those who deal mostly in cash to obtain one-off or refillable cards to be used to pay for things on its site. Venmo has turned erstwhile cash transfers into electronic payments. But these solutions mostly tear down limits to the addressable markets for their own products without necessarily expanding economic opportunity or promoting inclusion, while also often being based on internet and mobile technology not available to all.

Keith Beaty | Getty Images

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