On a recent trip to Paris I found myself in the 9ème arrondissement with a spare 30 minutes so decided to pop into one of Drouot’s auction houses.

If you haven’t visited Drouot, I recommend dropping in on one of their open auctions just for the experience. It’s entertaining, and there’s no expectation that you participate as a buyer (just don’t stretch suddenly before the commissaire-priseur yells, “Adjugé !”). Plus you might find a hidden treasure.

An old friend of mine used to visit regularly during his lunch hour. On one occasion, a live auction of a collection of renaissance art happened to contain a small Warhol sketch in the midst. Since all the professional buyers work under strict mandates, my friend snagged it at the opening price, free of any counter-bidders.  “Excellent achat, Monsieur,” the clerk whispered to him on way out.

Without going too deep here, these auction houses have three principal business activities: sourcing, appraising, and auctioning. The auctioning component provides the primary means of revenue, whereas the sourcing component represents a cost center. In the latter, auction house staff would typically visit an estate of say a deceased owner, eyeball the goods, offer the next of kin a bulk price for the whole lot of them, and cart them away in a truck. This is an oversimplification to be fair — there could be intermediaries for example — but you get the idea.

This sourcing activity provides a useful service to the next of kin during their time of grieving, who do not necessarily care to be bothered with clearing out all of grandpa’s old junk, however valuable it may be.

Today, the auction houses or similar online marketplaces (albeit with the former in decline at the hands of the latter), still operate with a certain degree of equilibrium between the supply side and the demand side. To put it bluntly, grandparents with a lot of valuable old junk are still dying, and youth interested in valuable old junk are still buying.

My intuition, however, is that this equilibrium will soon tumble way out of whack.

I witness for instance, in Japan — the eastern front in the massive demographic inversion — the sixth straight year of adult diapers outselling baby diapers. Most developed countries in the West will ultimately face the same effect of an aging population. Meanwhile, millennials have become known as the streaming generation, renting or borrowing more, and buying less.

So on the one hand, we have an aging generation of baby boomers, for the most part homeowners who have accumulated a substantial volume of stuff (especially in America). Then on the other hand, we have that generation’s heirs, the millennials, who for the most part do not possess the homes to horde it nor the hunger for buying all that stuff.

Supply will far outstrip demand.

I could imagine that the sourcing teams of the auction houses (those who haven’t been entirely disrupted) will no longer need to pay to cart off the deceased estates’ collections. They might even start charging for such a service.

For anyone interested in a bunch of old knick-knacks, retro clothing, family heirlooms, etc., it will become a real buyer’s market out there.

Now that I think about it, I’m going to register accounts on some of the handy mobile apps which facilitate closet clearing. Japan’s unicorn startup Mercari is one excellent example, France’s Videdressing it another, though local actors probably exist in every developed country.