I would say that I'm indifferent since I don't buy anything for Starbucks, but I'll say that the old adage, "Quality not quantity" applies here.
Even if they did sell coffee in that size, why would you want such a large amount of weak coffee?
I drink a lot of coffee at home, sometimes by the pint, but I find that the strength of the coffee is more important that the quantity.
I'd much rather make 4 cups of strong black coffee that remain hot than only make one large coffee that will be cold by the time I've finished drinking it.
As a takeaway soft beverage container, it's not even that large or convenient. 1 or 1.5 litre bottles are much better as you can screw the top back on and carry them around with you, but a large flimsy cup is just a pain in the arse.
But I suppose I'm missing the point of Starbucks, where practicality and quality take a back seat to the brand and establishment.