So I've been mulling over this one since Star Trek: First Contact first came out in theaters and mentioned the whole "no money" thing in place of the philosophy "Self Improvement" of on the big screen.
Then later slightly mocked on Deep Space Nine by Nog with Jake's whole "It means we don't need money." when he can't explain what the philosophy actually means.
The actual exchange (I bolded some interesting points):
Nog: It's my money, Jake! If you want to bid at the auction, use your own money.
Jake: I'm Human, I don't have any money.
Nog: It's not my fault that your species decided to abandon currency-based economics in favor of some philosophy of self-enhancement.
Jake: Hey, watch it. There's nothing wrong with our philosophy. We work to better ourselves and the rest of Humanity.
Nog: What does that mean exactly?
Jake: It means... it means we don't need money!
Nog: Well, if you don't need money, then you certainly don't need mine!
The exchange has always stuck in my brain for a long time and as I see the discussion on here and elsewhere about the how it might be impossible for the Federation could exist without money... what if it's just Humans?
The way I have seen it is that the United Federation of Planets more like the modern European Union, rather than a corollary to the United States of America. Now while the Euro is the primary currency of the EU, there are other currencies at large as well.
Perhaps that's where the rarely mentioned "Federation Credit" comes in. A universal currency, used by some members but not all. We know from the shows that not all things are something a replicator can make. The biggest example being Latinium. But seems Deuterium and Dilithium are in the same boat.
For example: The Bolians obviously (as of Deep Space Nine) have a currency based economy. The Bank of Bolias. When Quark is blacklisted from Ferengi Commerce; Bolians waiters replaced his Ferengi ones.
Also Voyager made references to the Vulcans having some sort of currency.
Then there are references to mining ops, private traders like Sirano Jones, Harry Mudd, Cassidy Yates and... Ugh... Okana.
In fact wasn't the Tribble an attempt to pay for a drink on K-7?
So to bring it all home. What if it's just the United Earth government that has for sure eliminated money. They just absorb the various costs that still exist in order to create what the humans call "Paradise." Other species in the Federation (and Bajor too once it accepts) keep their currency and probably have an exchange rate in both Federation Credits and possibly GPL after Grand Nagus Rom normalizes relations.
What do you all think?
I think a lot about the Federation's economy has been misinterpreted over the decades.
It's obvious in TOS that they use money. There are numerous references to "credits" as units of currency and various people getting paid, not to mention how much Starfleet has invested in Spock (sounds like a considerable amount).
If Cyrano Jones hadn't given Uhura the Tribble, she would either have had to pay 10 credits cash, or used the 23rd century equivalent of her credit/debit card. And yes, he did try to swap a Tribble for a drink. But by that time the market was literally saturated, and Tribbles had become worthless as an item of trade.
Fast-forward to the movie era: Kirk tells Gillian that they don't use money in the 23rd century. I interpret that to mean they don't use
cash. Yes, Kirk has some cash on him (his share of the money from the sale of his glasses, none of which was spent on the bus since he didn't have exact change). That doesn't mean that he actually has any idea what it's worth. He didn't offer to pay for the pizza, because he hasn't any idea how 20th-century customs work regarding restaurants (not to mention that since Gillian invited him, Gillian should take care of the bill). Kirk's food comes out of a synthesizer, for the most part, and doesn't cost him anything unless he's dining out at a non-Starfleet establishment. And even then, cash isn't part of the equation - the cost of the meal is just debited from his account and away he goes.
If the Federation doesn't use money, how do they compensate the military personnel in Starfleet?
They must do it somehow. Otherwise, Beverly cheated the trader on Farpoint Station for that bolt of ugly cloth. What a shame that Picard wasn't there to remind her that they don't use money in the 24th century, and she shouldn't be so acquisitive, since the cloth didn't suit her coloring, wasn't practical, and wouldn't help her to become a better doctor.
Or make donations in church?
Hopefully mainstream Federation society would have moved on from supporting churches in that way. After all, with everyone's basic needs taken care of, there should be no need for charities, and how does it "better humanity" to have fancy churches?
That has been my idea for a while now. Humans have gotten rid of money, because their tech produces everything easily.
But this now this bring us back to the usual conclusions;
Sisko is serving his customers for free. Data's housekeeper is working for free too. The guy or lady that removes waste extraction or whatever they call it, is doing it for free.
I'm not disputing that earth doesn't use money, only trying to know how do we explain this part? This is the most baffling part of the no money concept.
My take on this is simply that
Starfleet doesn't use money. If you work for Starfleet, all your basic needs are taken care of, and the higher your rank, the more "extras" you're entitled to acquire, if you want them. So an admiral would have fancier living quarters than an ensign, possibly a private estate... but the ensign would certainly never go hungry, be without shelter, medical care, adequate clothing, reasonable opportunities for recreation and leisure travel, and so on.
The problem is that Picard lives in this little Starfleet bubble and he tends to assume the rest of the Federation is like that. It's been demonstrated numerous times in the post-TOS series that lots of people don't live in a money-free world, even on Earth. I refuse to believe that Sisko and Robert Picard are just giving their food and wine away and their employees are working for free. That's ridiculous. They have to be compensated somehow. "Bettering oneself" only goes so far before a person wants more than just a good feeling as compensation for what they do.
Well, it may be that service for society provide the additional access to the resources - more than just basic goods. For example, basic food, housing, transportation are free. But if you want something non-standard - like your own spacecraft, for example

- you need to "work its price".
What
is the price of a spaceship? Picard tapdanced his way out of explaining that to Lily when she asked.
Just today, watching a poker scene in TNG it makes some sense that they're playing with their own money, otherwise it wouldn't hurt so much to loose or place huge bets.
Kinda odd, I know, but works for me.
Why would they play with their own money? They could have, of course, but why? That would fly in the face of "Starfleet will provide" and "we're all in this to better ourselves" stuff.
My overall take on this is that any society that's more complex than a small band of hunter/gatherers has to have some sort of economy to function. Even if it's just bartering goods or services, that's still an economy.
Look at Voyager. It wasn't too long after they were stranded in the Delta quadrant before an internal ship's economy developed: replicator rations and holodeck time. Energy wasn't unlimited anymore, so it had to be used for essential things first. That made the replicator food and holodeck time more valuable. The result was a new economy.