Here are the two most telling paragraphs in Ángel González's Seattle Times story about the explosive popularity of those single-serving K-cups:

“The convenience is amazing,” said John Berger, a 77-year-old Bellevue resident who was recently buying two boxes of Tully’s decaf K-cups at his local Fred Meyer. “You can get a fresh cup each time,” he said, adding that he owns two Keurig machines — one at home, and one at his vacation place in Montana.
The convenience does come at a price. At about 65 cents per cup, that Nespresso coffee costs about $59 per pound.

The story of K-cups is a story about class in America. They wouldn't be a popular item right now without a booming economy for the one percent, the same way SUVs became a trend in George W. Bush's tax-rebate America. The reason these incredibly wasteful products sell is because too many people have too much money.

K-cups are stupid. They're wasteful. Nobody buys K-cups thinking that they're being a smart consumer. They buy K-cups because they know they're paying five times the price of a pound of coffee, and they just don't give a fuck. It's neat. It makes one serving at a time. You just throw the cup away when you're done. What could be niftier? You need these stupid disposable things to remind yourself of how much disposable income you have, don't you?

One day we'll look back on these stupid fucking things as another wasteful rich-person trend, like McMansions and that one summer where every dipshit in a tie was careening around downtown Seattle on a Razor scooter. Maybe the next trend will involve pouring printer ink directly from the cartridge into the toilet?