Not only are the goods positional, but also much of the new work that's been created. The extra hours aren't replacing children on the farm or in the factories (the developing work takes on those jobs as a much lower cost). They're being created in professions like marketing, banking and civil law which exist to a large extent more to defend their employers' margins from competition than improve productive output. A corollary of this is that, purely theoretically, a four hour workweek might be achievable for the middle classes simply by trading those hours worked that have a negative impact on the economy as a whole for leisure. The problem is that nobody knows which half of their advertising budget is wasted (but there will be no shortage consultants willing to charge expensive hourly rates to offer an opinion), and everybody knows that even though their own exceptionally hard-working investment manager spent hours making the wrong bets against the economic downturn, somebody sat on the upside of that trade and everybody would suffer if there was no liquidity whatsoever.

Beyond positional goods, the other money-suckers are higher education and healthcare, which are both on the one hand arguably an extremely good thing for increasingly large amounts of economic surplus to be thrown at despite inevitably diminishing returns, and on the other hand utterly ridiculous in the US.