Sorry, I don't follow any of your reasoning here. Monopoly money is a low cost print with little detail on standard paper. People don't throw away foreign currency simply because they don't know what it's worth. I'd recommend taking a look at the psychology of cash to understand my point better.
Are you sure? If I find a single bill from a random country I assume the worth isn't a whole lot. Such bills get stashed in the souvenir box which may or may not be thrown out at any point when space runs out.
> I don't follow any of your reasoning here
I don't think the birth certificate analogy is that hard to follow. It's easier to hold onto a US-letter-sized document than it is to save a single bill that you should not place in a wallet.
