Ann: Annual Report to Shareholders, page-14

Mac wants to know "why do you think they would be hoarding gold rather than selling it? There are more practical ways of speculating on price escalation other than storing it."
I believe the answer to be twofold:
1 the (legal, but unorthodox) accounting methods used by RND and TBR allow Billis to stockpile the bullion, and only he know its true value, because we all have to guess at the production cost of the inventory.
2 There is no "they", only Billis, who is a goldbug and obviously waiting for the days when the gold price is multiples of current levels.

The inventory is not sold because here's no cash required other than to pay the dividends that we sort-of nagged out of him over the last few years. Billis himself doesn't want to receive monster (taxable) dividends. I would say that he's waiting to one day sell his shares in the companies (when POG is stratospheric), those shares probably CGT-free. ...........All this just guessing as to his behaviour, and I of course don't know the CGT condition within his family group entities.