If the company would have made $100,000 in profits but bought $100,000 worth of gold for $100,000 then they still have $100,000 profits. If the gold price changes, they'd have a bit more or a bit less profits, they also would have a bit more or a bit less of value.
If the company buys pens, paper, toilet paper etc. for their office that reduces the profits. If the company buys a computer that has to be written off over say four years, so their profits are reduced by a quarter of the purchase price each year.
If the company tries to game this - like if the four owners each have a child, and the company pays $25,000 for a drawing made by each of the children - the tax office will come down on them like a hammer. Same if the company bought gold for $100,000 and each of four owners took $25,000 worth of gold home and sold it.