Consider that their economy is supposed to be perfect compared to ours. They cannot describe it because if they could, then humans today would change their economy to match. It's why they can't say how warp drive works.
Whoever said their system is 'perfect'?
'Different' (and to my personal liking) would have been better.
And even if they could describe how the system worked, I doubt that humans in real life would change it to match.
Those in positions of power/control wouldn't want that kind of a system in place because for one thing, it 'reeks' of 'equality'.
As for Warp drive.
Solid theories exist on how it could work, but even if they knew how to make it, doesn't mean they WOULD in real life.
Consumer technology is decades behind the actual development.
This is one of the reasons capitalism 'thrives'.
It's point today is to milk consumers of every penny even if they are selling 'outdated' tech with minor revisions as 'new'.
Today, humanity is 'toying' in 'technological obscurity' and isn't even using THAT to it's fullest potential (we could have gotten rid of majority of problems decades ago with technologies at our disposal - let alone ones that were never released).
One of the probable reasons as to why Humans managed to 'advance' so fast after making FC with the Vulcans was because 'the betterment of mankind' factor (and working together).
The point of capitalism isn't 'betterment of mankind' (if it was, moon bases, orbital complexes, flying cars and quantum computers would have been in circulation by now - the tech exists, 'money' is what's keeping it out).
Recycling tech is how old by now?
We could have used it to be self- sustaining for a LONG while on garbage mountains throughout the world.
Need I go on?
As for my replies to T'Girl...
First off, I wasn't making an assumption when stating that "Federation ambassadors" don't automatically mean that they were from UFP member worlds.
I was effectively stating that we had no proof that Bolians were part of the UFP.
It's 'assumed'. I'm merely stating that we cannot make such an assumption especially if nothing in canon directly states it.
Regarding Sisko's restaurant:
The definition of 'business' could have easily changed from today to the late 24th century (or late 22nd century when the New World economy took place).
Besides, Sisko's father could easily be getting something in return (such as materials or nothing related to money of any kind) because he has a restaurant.
Besides, he can still have a restaurant and call it that while inviting people to eat his foods, because he LIKES TO DO IT.
It doesn't mean he was getting paid or receiving money for having a restaurant.
As for Kassidy... there are numerous people who work today and not get paid at all or receive anything in return.
Kassidy could have been getting enough materials and resources to run her freighter, though nothing in monetary reimbursement.
Or she could have been one of those humans who 'prefers' money or currency based economy.
Just because she works within Federation space says nothing... lots of people have the right to pass through Federation territory.
As for Bank of bolius... you are using contemporary terms and definitions and superimposing them into a time frame that could have changed their meaning.
So what if the 'bank' of bolius was robbed.
It doesn't mean it was money that they stole.
It was never said WHAT was stolen, so making an assumption that it's 'money' simply because of one's personal interpretation that a 'bank' means storing 'money', is a bit ludicrous, especially since we are talking about an alien culture, 400 years from now.
Oh yes, I can see where applying current terminology and points of views to THAT can be useful (not).