To play's devil advocate and stop the circle jerking, let's do an intellectual exercise and try to think about why this might not be the dumbest decision ever. Maybe it could be more than just a ploy to increase sales of 1st party cups. Maybe it's about Quality control.

I grew up playing a lot of Nintendo games. SNES. N64. Gamecube. Wii. There was one thing I noticed about it. Nintendo always made the best stuff. They made the best controllers. The best games. The best memory cards. I had a 3rd party memory card that said it stored "56 blocks." But if you tried to put more than 20 on it, you'd sometimes find your data magically lost in the morning.So despite the GNU/Linux ethos (I'm typing this on a Linux machine), freedom to use 3rd parties does not always give a better user experience. More than that, I found Nintendo also had to approve every single game and accessory that was compatible with their system (seal of approval). So even that was considered the good stuff. This seal keeps a certain floor of quality control. Back in the days of the Atari, people were making all sorts of shit for it. Stupid consumers would buy it, use it with their Atari, and be frustrated. Nintendo forbade this and made sure everything that was associated with their product met a certain standard, thus giving a good experience. So maybe, Keurig will use their DRM for this. A way to help consumers, perhaps, figure out which cups are good.