It's not a stereotype and it's not really a mystery.
Licking or wetting your fingers for this purpose has been a standard practice across the globe, when people are dealing with turning pages (e.g. for accounting), counting tickets, coupons, paper money, etc. It was never just something older people did (except in the sense that the practice is not as common now, as people in the US and Europe don't need to do it that much anymore, due to changes like reduced use of cash, etc.).
So, you might not have seen it since the need is mostly obsolete in most of the west, but it's still a thing elsewhere, and was very much a thing in the US and Europe too until a few decades back.
So much so, that there were office gadgets made for this, basically a base holding a small sponge, that you would add water to, and use it to wet your fingers for counting/changing pages. They're still very much sold:
I'm not stranger to licking my fingers when dealing with cash, or licking stamps and envelopes, etc. but the way some old people do it was always a little mystery to me. I'd see them taking a second or three to quite conspicuously stick their tongue out and slowly lick their finger every single time before turning a page or a banknote. I always figured it's just a force of habit, but they're doing it in maximum power-save mode, and are way past giving a fuck about how gross it looks to everyone around them. I never considered that maybe they really need to do it this way to keep their fingers moist.
(That realization scares me, as it means I too might become an obnoxious finger-licker in a few years.)
>I always figured it's just a force of habit, but they're doing it in maximum power-save mode, and are way past giving a fuck about how gross it looks to everyone around them.
That's the other thing about it, when it was being done in the past: people weren't so appealed by having bodies, or frightened of life and anything that's not sterile.
So they weren't as grossed out by everything - including a person merely licking their fingers to count some pages or notes...
There’s a whole little range of forgotten/dead products for this. It looks just like a tiny pot of Carmex or other lip balm and it coats your finger to make it that tiny bit more grippy to make handling loads of paper easier. No idea what it’s name is haven’t seen it in 20 years since I stopped having to hang around the church offices while my parents did choir practice.
Honestly, and in line with a reply upthread[0], fresh saliva may be more sanitary. I mean, it has some non-zero antimicrobial properties, plus it doesn't accumulate random stuff that could grow over time.
Yeah, I'm starting to understand why old people may be past the point of giving a damn about the optics.
The "sanitary" replacement is a wax, I always just knew it as sortkwik (? It's been a while), that you dip your fingers in. I'm sure it's still a thing for literal paper pushers to this day.
Sanitary in quotes since I'm not sure a pot of wax collecting stuff from your fingers for months or years is much better than licking.
Those sponges can be seen at every Japanese supermarket, to assist in opening tear-off plastic bags, because licking one's fingers is taboo. In a similar way, birthday cards need to be closed with tape rather than licked.
I think the idea is that you aren't putting your dirty fingers in your mouth, or your spit on stuff that other people might handle. The latter really doesn't matter scientifically I think, but the former probably does.
People put their fingers on all kinds of things other people have touched: doorknobs, elevator buttons, shopping basket/cart handles, etc. Adding a moist pad to that isn't going to change anything. Keeping people's hands out of their mouths, however, might.
I think COVID-times ended that habit quickly around my city. I used to lick my finger to open plastic bags on the supermarket and now try to find something wet instead - usually alcohol bottle.
(I'm asure it was always a bit nasty but when it became a deadly move, my habits finally changed...)
Licking or wetting your fingers for this purpose has been a standard practice across the globe, when people are dealing with turning pages (e.g. for accounting), counting tickets, coupons, paper money, etc. It was never just something older people did (except in the sense that the practice is not as common now, as people in the US and Europe don't need to do it that much anymore, due to changes like reduced use of cash, etc.).
So, you might not have seen it since the need is mostly obsolete in most of the west, but it's still a thing elsewhere, and was very much a thing in the US and Europe too until a few decades back.
So much so, that there were office gadgets made for this, basically a base holding a small sponge, that you would add water to, and use it to wet your fingers for counting/changing pages. They're still very much sold:
https://www.amazon.com/money-counting-sponge/s?k=money+count...