Treasure is value removed from circulation. When it circulated it was just money which, of course, engenders a lust of its own. Money may grow over time due to its ability to be employed as productive capital and so lay claim to the surplus value extracted from labor.
Buried treasure, as the bible tells us, has no such power and so is condemned everywhere but in the heart of the miser where it is seen as power without risk. It lies always ready to do his bidding but never consumed or exposed to a hostile market.
Time plays a double game on buried treasure. Its circulating sibling draws interest and grows. Of course it may also fall prey to piracy and panic but on average, over time, it increases. And so, relatively, the buried value diminishes.
As the hoarder grows old and forgetful and, finally, dies, perhaps taking the location of his hoard to the grave, treasure disappears.
But, if we speed up our capitalist time machine, we might see a general thinning out of value. Production grows exponentially but the metallic base grows more slowly. While a dormant bank account withers (and, in the modern financial world, will almost certainly disappear) the classic forms of treasure may often become more valuable. If they are marked in time, if, that is, we can distinguish them as survivors while their contemporaries are known to be destroyed or lost they may also gain value by their rarity.
None of which makes for an enjoyable Game Night, just a dull essay. What is it that really gets our peckers up about treasure?
The key to the "charm" of treasure is the break in the chain of title. Classical economics teaches us that value is exchanged for equal value in the system as a whole. What's the fun in that? Might as well play Monopoly. Treasure represents something for nothing, an instance of a pre-market, mythical transaction. Before the child understands trade she understands finding and taking. Finding the lost and abandoned and taking without payment, the principles of archeology and piracy.