I disagree. Who uses their Gold or diamonds? Both materials actually have industrial use, but if that was their only purpose they'd diminish in value. Nobody would dangerously venture deep into the earth to gather them. Their value is that people hoard them on their fingers, ears, necks, wrists and in their safe. The more people hold btc like some precious stone the more valuable it becomes and more scarce.
Edit. There is around 0.0028 btc for every human being. But almost everyone, even very poor has some form of precious metal or stone.