The commodities trade is driven by
people needing those commodities. Right? Like, Kellog and Absolut
need wheat. They
need them because their business relies on them. They are willing to pay a premium, to make sure their supply will be there when it's time to make cereal or vodka.
(interesting aside, the best heuristic i ever learned on how to get good vodka, look up the manufactures headquarters/operations location on google maps, and if you don't see grain silos, don't buy the vodka)
Who needs bitcoin? Honestly not many people right now. The speculative boom is that, in the future, it becomes internet-cash. Then people will need it, they'll want it a lot to buy things in the internet, and that's fine. If they do, then the value will go up.
However, aside from the fact that bitcoin is absolutely not able to handle cash-like transactions at all, there is still no reason for normal people to speculate on it now. If it becomes the de facto internet cash of the future, then, cool, you just exchange for it in the future.
The idea that anyone could ever anticipate the future demand of a trivially replaceable ledger of exchange is... honestly insane. I'm not saying it's not worth speculating on, but please, god, don't put any serious portion of your investment portfolio in those types of arbitrary bets!