Bitcoin's usage as a payment system for commodity value transfer is a more appropriate use of its abilities.
Paying for coffee is nice, but I think it is overqualified for that role. Think Miggy Cabrera being a little league coach instead of playing for the Detroit Tigers.
If oil, pork bellies, oranges, precious metals, and other popular commodities use Bitcoin then I think the true value of the Blockchain will come to fruition. Big value transfers between company A and B should use Bitcoin. No charge back, proof of payment, instant payment, low friction, these things are common sense. A Six Sigma project showing the clear advantages of Bitcoin over fiat transfer mechanisms would be a trivial task.
Bitcoin would also provide many benefits for inevitable corporate bribery transactions.
paying for coffoe and products should be a big use. but your idea of using it to trade commodities such as beef, wheat and oil. would be a great way to make bitcoin pegged to a kind of "cost of living" instead of pegged to the dollar.