You made me laugh @argentino, but the story is exactly like that!
It is a national tradition, although I cannot endorse it 100%, it is very likely that the lack of money in the last days of the month has contributed to this tradition that is ours.
Just a few days ago I heard an Argentine journalist who is in Spain and also traveled to Italy and asked if the history of gnocchi there also had that curious tradition of putting money under the plate but it seems that is not the case.
If the Italians make exquisite "gnocchi" with a variety of sauces that are the envy of the gastronomic world, but putting money under the plate and eating them every 29th of the month, no, that is exclusive to this particular country, so crazy. as dear.
Wow. I got it right. Nice!
They are so different from noodles (pasta). I did not gain any sums of money that I was not expecting as of yet, but I am not sure if it was supposed to come out of the sky or just by dumb luck.
My grandmother said: Rome was not built in a day. The money is coming, let's not despair.