Star Trek economics are just plain bull shit, any society who has the ability to create food or other items by the expenditure of only energy has no need of much else. I remember a quote, if a race could materialize star ships they would not need too and this is where Star Trek's future always struck me wrong, where is the limit to replicators?

As to the point of are were on a post scarcity economy, well we might be in some Western cultures but it does indicate quite clearly that given nothing to do far too many people will excel at it, worse when they do do something it will be to eat. Society will need to adjust those who just take to find something to do with their time. It might not earn them money or much but they need an activity to avoid end up looking like an extra from Wall-e.