I don't really believe that luxury cars or jewelry are inherently evil and won't defend those claims. I gave those as examples of (obvious) reasons people might object to those things.
Clearly some ppl buy expensive things to show off, but I dont think it follows that their intention is to demean.
I don't think it matters what the intention is. Our society universally denigrates the poor and elevates wealth to a virtue. Anything that contributes to that has got to go.