I am on the fence about k-cups. I use to make a partial pot of coffee at work in the drip machine. Sometimes I would drink it all, often they would be a cup of two left. As well it would sit hot for at least three or more hours each day. I did a calculation at one point the energy used and wastage of a k-cup vs drip machine. It was not even close over a year. I had to estimate the energy for the cup itself but the k-cup used about a quarter of the energy as it was only on during the making of the coffee and you would only make what you wanted. No wastage.

Simply put, the k-cup resulted in about 1/4 the carbon footprint of drip coffee in my situation. Personally I think people didn't really think this thru well and just jumped on it as being wasteful without doing any calculations.