I drink Starbucks daily. I would love to see this. I can't imagine using Bitcoin in a scenario like this. If this happens and other retail outlets are forced to compete Bitcoin will be accept around the world almost instantly. Very exciting. I hope it happen soon.
I wonder if a single order of coffee will be much more expensive if you use Bitcoin during your coffee break. To think the minimum mining fees or transaction fees that will be included in the payment in which i think it will be more expensive than using the fiat currency for the instant payment so i suggest paying bulk orders will be much practical way of using Bitcoin in this kind of establishment.