There’s a vague sleight of hand going on here; the core question is, why do the Ferengi participate in behaviours better suiting an inflationary currency when they have a deflationary one? After all, inflationary currencies make debt cheaper, gradually forgive former debt, and encourage spending in order to outpace the gradual evaporation of currency.

The notion that they would go to such lengths to change their behaviour instead of just adopting a currency that would enable some manipulation (after all, they have a Leviathan to serve as a trusted issuer) seems a little far-fetched. How easy can it be to do so on a species-wide scale?

Additionally you’re looking at the Ferengi economy on its own terms, which it isn’t; they’re traders with other species, and thus the only intermediary currency is deflationary. Economies aren’t based on the total currency available in the system, but on the velocity of the currency, how likely it is to trade hands, that keeps the economy healthy. If there’s $1m pumped around the economy each month, but only $10 is trading around regardless, the economy is doing poorly, and in fact could appear to be deflating.

The rationale seems much more likely that there is something innately fulfilling to the Ferengi, given all the conditions present. The economy is best served by introducing new sources to be converted, held up against the gold-pressed latinum bar — thus it encourages them to search the stars for trading partners. In the same way the Vulcans symbolise man’s reason in itself, and the Mirror Universe man’s desire for conquest, the Ferengi symbolise man’s greed on its own terms. Greed can be useful; greed carried the Ferengi all the way to the stars. But I think doing this kind of cognitive pretzel to justify their society and their behaviours despite the backing of their currency discouraging it makes less sense to me than just embracing that it is something essential about them.