The vault is another fad that eBay is chasing. The allure of collectibles as an investment has never proved to be a good bet. Very few collectibles actually garner consistent returns or grow in value in an orderly fashion. When collectible markets crash, and the invariably do, they can take decades to rebound if they rebound at all.
Imagine if in response to the Beanie Baby craze, eBay had built a vault? Tons of moldering stuffed animals with nowhere to go.
What happens when stored items are worth less than price of storing them? Yes, some people store extremely valuable works of art in vaults for investment purposes. They are not your average eBay buyer 🙂
