Macquarie University lecturer Dr John Selby has highlighted downsides of a total reliance on digital payment systems and he contests they are particularly relevant to regional areas.

Network reliability issues because of outages or natural disasters, and hacking were among the concerns he identified.

The member of the Optus-Macquarie University Cyber Security Hub says there are situations where "cash still has benefits".

So when the COVID-19 pandemic has first come to everyone's attention, earlier this year, there were concerns that surface transmission of the virus may be a major source of infection for people.

So that's been one of the concerns for the use of cash is that the virus could last, in theory, for several days on plastic, and therefore if people were paying using cash, that could be a way that someone else would touch the note, and someone else would touch the note, and then there would be infection.

But what we've seen in our lived experience with the virus seems to be there's more infection from airborne transmission of the virus, than from surface transmission...We've not seen, as far as I'm aware, reports of transmission from handling of money.

It's a possibility, but we've not seen evidence of that.

...Now that may be a chicken and egg thing where if people aren't using cash, therefore we're not seeing a lot of transmission, or just because Australia's been very fortunate and so far, the number of people who've been infected has been on a global level, quite low.

I think they are.

Particularly, a cashless society where you use a digital payment system, relies on the assumption that you always have access to high speed reliable internet.

And we know in regional areas of Australia, that is not always the case, and that if transmission networks get damaged, it can take much longer to repair them in country areas of Australia than it does in the city, where you've got a denser population or perhaps more redundancy in those networks.

So if you had a purely digital payment system, and the network went down, or it was hacked, then it might mean that people were unable to make transactions, unable to buy their meals or do the grocery shopping, or pay for needed equipment for their farm.

There's the concern the cashless payment system is vulnerable to hacking, so that we've seen where people have had digital wallets and millions of dollars stolen from them, particularly people who hold cryptocurrencies. But if you are all using a digital wallet attached to your phone for example, as compared to a cash-based system, then there would be a risk that your phone could be hacked.

We've seen mobile phone porting, unauthorised porting occurring, particularly with the two-factor authentication systems, with SMSes, where those have been intercepted by criminals.

And one weakness can affect a great many more people when it's a digital payments system, as compared to cash, where there's resilience in redundancy and each person has a separate physical wallet. You can't mug 100,000 people in one day, to pickpocket their wallets, whereas if it's a digital wallet, and there's a flaw that's discovered in it, you could in theory hit 100,000 people in a morning.

So the distributed, resilient nature of cash is something that people tend to take for granted, but it's not something that's a benefit every day, but it's a benefit when it's an emergency, when there's fires, floods, natural disasters, for example, when infrastructure goes down, because people have a means of continuing to transact.

And with the effects of drought and fires and floods being worse and getting worse, decade after decade in recent times, I think that's another reason why particularly people in country areas might want to resist the push to remove cash entirely.

There's a couple of things, one is that trend towards reduced cash usage is significant but it's also perhaps a generational thing, where the older members of society have been more keen to use cash. And particularly those who might have concerns about spending habits, so there's sort of a digital divide in society, and digital payment systems favour the highly-educated, the wealthy etc...

The idea of understanding that money requires work is something that parents educating their children these days has been an interesting one. I've observed with friends that the children just think that you can get things by tapping a piece of plastic, they don't realise they have to do the work to earn the money, it's not an immediately obvious thing to a young child.

Whereas giving a child pocket money, and getting them to learn, for doing chores, they doing so many chores, they get a bit of pocket money, they then can make decisions and learn to make choices.... If you want to buy this lolly today, you can't buy that burger tomorrow.

That's something that handling physical cash gives a concrete understanding of, for a child, whereas tapping a piece of plastic is more abstract.

That they need to think not just about the ease and convenience of digital payment systems when everything's working fine, but about the way in which they would be able to continue living their life if those digital payment systems were not working.

Do they have some cash reserves that they could use to go shopping to buy food, other essentials in a situation where a bushfire has taken out the telephone lines and the payment system doesn't work, for example, or a fire or a flood, et cetera.

Also, that their digital payment systems require access to the internet, which means that cyber attacks can be launched against them.

So they don't just have to be concerned about a local person causing them harm, stealing their wallet, they might have to be concerned about a hacker on the other side of the planet.

So for those reasons, I would say that I think cash still has benefits, and that we need to think very carefully as to whether the push towards digital payments addresses all of the problems and issues cash helps solve.

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