This is one of the prime reasons I think the government and society in general would want to make the deliberate conscious decision to retain money and a economy that requires it to be earned through employment..
Well, maybe, but I don't see how an artificially-enforced economy would be stable for very long. Sounds a lot like communism, if you ask me. Just because some people at the top think it's a good idea, or a necessary one, doesn't mean it'll work for a long time.
The free rider problem may not exist for the 24th century UFP economy, because the costs could be so low that nearly everyone can be a free rider without any negative effects on the production of public goods.
It's an odd fact about the 24th century, but still a fact, in case you haven't noticed they have no robots, no mobile automation, Data is a one off and Captain Picard regarded the exo-com's as something highly unusual. This is part of what leads me to believe that they actual DO have a paid work force. They don't have robot because they have people to do these jobs.
I've noticed that there are no
visible robots depicted in Trek. It's not a problem, though, really, because why would they ever have an episode about the machines that work in the background on menial tasks? They wouldn't have to be artificially intelligent; in fact, that would be a disadvantage, since you don't need or want a robot with Data's intelligence (or even B4's) to wrap cable, or paint bridges.
As for the exo-comps, they were described as
common industrial robots, modified with decision-making algorithms and learning capability, but not intended to develop independent thought. Surely there are many dumb robots like the exo-comps' ancestors working in the background of UFP society. We just didn't see them often.
The solution to the "no robots" paradox in Trek, though, is nanites. Microscopic robots could surround the characters of Trek, working in the background all the time, and they wouldn't be visible. Certainly nanites were common enough for Wesley Crusher, a gifted high school student, to work on them as a science project.
I think his point was that, in reality, we're not currently living in a scarcity economy, not in the west.
Oh, there's no question that we have an abundance of goods and services in the West. But are we in true post-scarcity situation? I don't think so.
Something that you and others have left out of your position, your argument -- and this might seem very obvious to you -- but why do you make the assumption that a post-scarcity economy would require no money?
Well, what's money for?
I exchange money for goods and services that I cannot provide for myself, since I lack the time, energy, and skill to, for instance, grow my own food; I earn money by providing service to others that they cannot do for themselves. Economics is a cycle of interdependency.
But what if food and clothes were provided by a replicator, a replicator owned and controlled by me? I needn't spend money on those necessities. My expenses would be lower, so I'd have a lot more money in pocket, making me relatively richer without increasing my salary. If this were the case for everyone else, too, then inflation would rise, making currency worth less. If this situation were to spiral, at some point currency would be worthless, making the tracking of money exchanges not worth the effort. The replicator eliminates a great deal of the dependency of humans on other humans for support and survival.
For my own part, though, I don't necessarily think a post-scarcity economy would have to be moneyless. It's possible that even in a post-scarcity economy, some form of market economics with currency-based exchanges would still occur. For instance, any activity that required human oversight would require someone's time be occupied by that activity. Time would still be a scarce resource in a post-scarcity economy, such that a unit of currency could be based on it.

In that case, how much your time is worth would depend on numerous factors, including your skill set and how much free time you have available already. Unambitious slackers with copious free time wouldn't be able to charge much for their time, since they have time in abundance and no particular
need or drive to do anything but vegetate. Ambitious and intelligent people would have less free time, and more valuable skill sets, so that the time they spend overseeing activities or helping others would require some kind of time-credit compensation.
Whether something like that scenario exists in Trek is unclear, since the familiar Starfleet characters aren't living or working in the civilian world, and extrapolating from daily life on a starship to the life of the average citizen is a perilous endeavor.
Still, I think that if the characters say "We don't use money" and that "the economics of the future are somewhat different", then I don't see why we shouldn't accept that. If the Federation still uses currency and scarcity-driven exchanges, then they're not "somewhat different", they're not different at all.