I remember seeing it as a kid, and even then wondering how one can trust someone writing such a cheque. This is the case whether I say "1gram 24k gold" or not.
The free market is quite capable of revealing who to trust and who to relegate to sweeping streets and collecting rubbish. Eventually, credible groups will gain market share. Deja Vu
Then these groups will get power, all power corrupts, they will find ways to appear credible, while getting more and more sneaky. Then they invent something called "banks". Deja vu.
Grimm's tales and other ancient histories bear a reflection of what we see today. The old tales and myths are coming to life with the admonitions of yore. Words carry heavy forces.
Bad moments loom darkly for anyone using the word "bank", "loan", "interest", etc. "I will make a bank for your deposits" may be enough to get someone crucified. for a decade or more.
Many of us recognize the tales of vampires, demons, and exorcisms were 'best effort' to pass forward knowledge about unspeakably horrific entities that prey upon gullible populations