I dunno I'd assume that an organization the size of Starbucks can probably afford to have a few folks dedicated to their supply chain economics separate from the coffee house operations and marketing folks.
I have to confess I'm a little baffled at the story here, though. My understanding is that it's often more important for a large business to have knowledge of future raw materials prices than strictly the lowest possible prices. So it should be expected that buying coffee futures will do more to smooth out the ongoing price of coffee than to minimize it. Sure, it would be nice to minimize the cost of coffee beans and I'm sure Starbucks works hard to do so, but to if they (or anyone) could constantly be perfect coffee price predictors, they wouldn't need to produce coffee to make money.
Starbucks, being as big as they are, may simply have felt that they were big and well-informed enough that the risk of self-insurance made more sense for them... a decision which is easy enough to snipe at ex post facto, but may still have made more sense.
Plus, the buckets of money thing is a canard; Goldman has to earn a percentage on their capital, just like anyone else. If they have 10X as much equity as Starbucks, they need to earn 10X as much net profit to get the same return. And ceteris paribus, that means taking 10X as much risk.