I see quite a bit more stuff among the regular middle classes that looks like pure signaling waste...
To take another angle on this, assume for simplicity that anything not wasted is "reinvested" in signaling. E.g. a Prius is somewhat practical and not just a signal, so more is spent on lawn care than if an SUV was purchased.
An important factor will then be willingness to borrow and be in debt, and Orthodox societies have a very, very high tolerance for this. One explanation would be the prominence of the LORD as provider.
There is one major signaling factor that the middle class does "spend" far more on, and that is aversion to certain government benefits (but not others, such as mortgage based tax benefits).
I was browsing my RSS feed, as one does, and came across a New York Times article, "A Village With the Numbers, Not the Image, of the Poorest Place", about the Satmar Hasidic Jews of Kiryas Joel (NY).
Their interest lies in their extraordinarily high birthrate & population growth, and their poverty - which are connected. From the article:
From Wikipedia:
Robin Hanson has argued that uploaded/emulated minds will establish a new Malthusian/Darwinian equilibrium in "IF UPLOADS COME FIRST: The crack of a future dawn" - an equilibrium in comparison to which our own economy will look like a delusive dreamtime of impossibly unfit and libertine behavior. The demographic transition will not last forever. But despite our own distaste for countless lives living at near-subsistence rather than our own extreme per-capita wealth (see the Repugnant Conclusion), those many lives will be happy ones (even amidst disaster).
So. Are the inhabitants of Kiryas Joel unhappy?