Is "licking the finger" to turn pages a generational thing?

I noticed that the only people who lick their finger before turning pages in a book, newspaper, or magazine, are usually at a minimum age 50 and up.

I don't see teens, twentysomethings, or thirtysomethings doing this.

Was this something taught several decades ago, perhaps on an institutionalized level?
Update: Sir Studley Smugley: Hey now -- don't get offended. I wasn't criticizing anyone, I was merely making an observation.

I too tried to impersonate my grandparents & parents by doing this, but it just didn't feel natural or sanitary, so it never caught on.
11 answers 11