In my experience what Paradigm2020 describes is very much the norm around the world.

> and briefly worked in a bank in,

I suspect this might be where the confusion stems from, if you're thinking of places where people go to banks you might be thinking a bit too fancy.

I'm thinking of stuff more like this https://www.youtube.com/watch?v=iCDQpm6f_pU

>According to that article it has nothing to do with condition, but with the lack of anti-counterfeiting protection on older notes.

I'd say the age of the money has everything to do with condition, and it matters a lot.