Unfortunately, the oncoming 'train' of a cashless society can neither be slowed nor halted. The world population will have no choice but to accept it.
There are many reasons that a cashless society would benefit government, businesses and many individuals. First and foremost is it makes cash-based business far easier and reliable. Whether an Amtrak lounge car or a fast food business, the problem of employees making incorrect change is erased. I long ago gave up trying fix their mistakes at fast food restaurants. In the dumbed-down society of today where clerks can't make correct change when the amount is shown on their screen, eliminating cash eliminates (not 'fixes') the problem. Cash drawer/shift checkout procedures will be reduced to seconds rather than 5-10 minutes, based on the situation. As night auditor at a hotel some years back, it was common to have the food and beverage manager hand me $3-5,000 cash received from cash bars in our multiple banquet rooms and it was my job to double count it, put it in the safe, and make appropriate accounting entries. Did anyone pocket some cash? Who knows? In a cashless society, all the funds were accounted for and collected at the cash register. A couple of button presses later, 'check out' was done.
On a larger scale, cashlessness also simplifies large retail operations. Just as going to a bar code system years ago simplified checkout processing and reduced keying errors, going cash free eliminates additional errors and thefts. And yes, sometimes the amount charged at the register for an item doesn't match the sign on the shelf, but it's up to us, the buyer, to catch it, not the seller.
An even bigger benefit of a cashless system is the elimination of illegal activities always conducted with cash. Whether it's dope dealers selling on the street or smuggling, the 'cash' would have to be recorded somehow. And bribes? And money laundering? No longer possible as all business income will be handled by the computers. And under-the-table payments to workers or for bribes...gone. Just as each sale must be conducted via computer, so, too must every income for every business and indvidual be recorded on computer as well. Needless to say, whether Apple-pay or other similar platforms are used, all your 'money' will be 'on the computer'. I think it's safe to say that just as our cell phones track our location, calls we've made and web sites we've visited, it won't be long at all before all our spending is recorded by 'big brother' and monitored by those interested.
So, for the large majority of the US population that is already using credit and debit cards and has direct deposit of our paychecks, it's not a major leap. And yes, giving a tip to an SCA will require him or her to have a scanner of some type to take the 'money'.
But there's a significant population that can't or won't have a credit card or debit card. A now deceased friend of mine found out the hard way that having a bank account anywhere would result in its being drained by the child support back payments he owed. So he was forced to work under the table and get his Social Security in check form. When Social Security switched to direct deposit or debit card, he opted for the debit card and pretty much cleaned it out as soon as it was received. That at least limited the 3 states taking child support to getting it 'up front' from his Social Security amount before the left over was put into his account. I have a couple of formerly homeless friends who still refuse to get a credit card or debit card and except for Social Security income, they work under the table.
The downside of going cashless is the small vendors such as those at a flea market or even the food truck operators. Ever watch all the line-slowing-down activities necessary to take a credit or debit card at one of those operations? What about various vagrants begging for small change? Like far too many government-run programs, it's the 'small guy' that gets hurt.
I also think back to one of my former co-workers that had direct deposit like the rest of us and a debit card. His problem was that he didn't fully make the connection that the debit card was just like cash. So he'd put a bunch of small purchases on the card and then raise Cain the he was being hit with overdraft charges by his bank. Like many people, myself included, I first see how much money is in my wallet and make spending choices based on that number. That's why I, too, will NOT have a debit card. It's similar to the 'trick' used by casinos to convert your cash to chips. It's so easy to think of them as 'chips' rather than dollars. I avoid casinos, too, as I never go home with any of THEIR money in my wallet.
Perhaps the biggest problem I see with a cashless society is an EMP bomb or other means to shut off all our computers. Nobody has any 'cash', so everything goes to a barter system or you starve. Alternatively, we must all be micro-chipped (mark of the beast) to conduct any business transactions. I don't think any of us would want to be around in any of those situations.