not being very popular doesn't mean the goods are useless, but indeed the use of the goods is rare and very rarely traded, only a handful of people like art, but this is different from commodities which are traded every day, of course it covers a fairly wide market, and many people use it.
I think the main crash is items that are not really used.
The market for Art and Commodities are very different. Commodities, like Oil, Metals, and also Orange Juice, are based on actual demand for the actual Commodities that they are. Art, althougn their real fair value is how much the market demands for them, is based on a sort of "scam" that artists, dealers, and collectors participate in. There's no actual utility in them. Bitcoin was in the same situation during its early years until the Silk Road was built which started the revolution for other Dark Markets to be built.
