Where are you getting this "one cent?" More likely power plants cost tens of billions to build and many millions for yearly operation costs, these cost being past along to the consumers..
In a single-payer economy, the government pays for the power plants
on behalf of the consumers. The consumers only have to make sure they're contributing enough in their day-to-day work and labor that the government has enough to make all of those payments. Apparently Earth is productive enough that they have all of that and plenty leftover, so nobody worries about it.
Earth is such an insanely rich planet that they never have to worry about the cost of things like powerplants and food production because no matter how much it costs, they (collectively) have WAY more wealth.
That's what it means to live in a post-scarcity society: you have such an abundance of everything that the costs don't matter anymore, and you can afford to be sloppy in managing your resources. It's kind of like how some people are rich enough that they can go out to eat at a restaurant and never once give any thought to how much anything costs, because they know that no matter how much the bill is, it won't even come close to making a dent in their bank accounts.
Replicators eat power, and the same for holosuites, same for use of transporters, other things too, future civilizations will use energy.
And Earth has such an abundance of energy and material wealth that they don't CARE how much energy is used, because they have 100x the money needed to pay for it all. They aren't going to nickel and dime the end-user consumer at replicator terminals because even if they COULD distribute all of Earth's wealth evenly throughout the entire population, they'd all basically be multi-billionaires.
Thus asking them to pay 5 credits for the use of a replicator would be an unnecessary nuisance. There isn't ANYONE on Earth who can't afford to use a replicator, and if there is, there SHOULDN'T be, because Earth has such a ridiculous abundance of wealth that we might as well just GIVE that poor sucker a million credits just for being such a swell guy.
It's a really simple concept here: Earth can afford to go without money because Earth is insanely RICH.
Bartenders and waiters/waitresses will want to be paid. Mortgage-lease-rent to be paid. Utlities to be paid. And don't forget insurance.
Not in the 24th century on Earth. Being a bartender (or a chef, for that matter) is basically a hobby and probably subsidized by the Earth government for all of your expenses. Mortage-lease-rent also implies the need of land owners to make money from their control of the land; if land owners don't NEED money, they have no reason to charge rent.
And the point was, Uhura possessed money to make a personal purchase.Are you admitting that there was money use in the 23rd century Federation?
Money was in use everywhere in the 23rd and 24th century. Just not ON EARTH.
In fact, this is a good rebuttal to Timewalker's curious argument about this being purely a "Starfleet" thing. Even Starfleet officers sometimes use money when dealing with foreign nationals, mainly because they're too far from Earth for the Public Pool to cover their expenses. So they have to use their own personal cash for that. It's not clear HOW they acquire that kind of spending money, but I'd venture a guess that Starfleet actually DOES pay its officers a salary that they can either accept (as Worf and O'Brien obviously do) or donate back to the Earth Universal Purchase Fund (as Picard and Riker probably do).
Here's an interesting question: Who paid for Geordi's visor? I actually kind of doubt that's standard Federation technology since he's the only one we ever see using it and Dr. Crusher isn't totally familiar with it. I'd bet he had to hire a specialist from another Federation or allied world, and he probably had to pay up front for it.
Maybe it came out of his mother's salary?