> they don't simply act like Smaug and sit on a pile of gold coins

That's because a pile of gold coins does not make money. One makes money by investing the coins, not investing in coins.

I always thought Smaug's hoard (as depicted in Jackson's movie) was beyond ridiculous. If it was unleashed on the economy, the price of gold would drop to the point you could pave the roads with it and make sewer pipes out of it.