This might blow people's minds but maybe a lot of people buy K-Cups even inspite of knowing about the alternatives and the relative costs/benefits of both.
Single-serving machines require near no cleaning, minimal setup, you can change drinks literally between cups, it is ready in 60 seconds, takes no space/are portable, and they remain much cheaper than Starbucks/McDonalds/Dunkin Donuts coffee (15c/cup Vs. 99c/cup or more).
Here are the steps to make coffee in an AeroPress:
1. Grind coffee
- I do this in bulk with a big grinder, and have fresh grounds for the day. You could also buy previously ground coffee.
2. Put filter and grounds into AeroPress.3. Wet the plunger.
4. Use a boiling water tap to pour over coffee.
5. Stir 10 seconds.
6. Push the plunger down, using air pressure to force the water through the grounds.
- this should take ~30 seconds to get the optimal flavor
7. Remove cap, plunge grounds out of the squeaky clean tube (remember, we just forced an inverted rubber stopper through the containment, cleaning it pristine)8. Rinse cap
9. Enjoy amazing, and amazingly strong, coffee/espresso
Process takes me about 30 seconds longer than Keurig.
But if you do have a sink, there's no excuse.
What matters to most people isn't that Keurig takes 60 seconds (or whatever) to make a cup of coffee, it's that it takes 60 seconds, including about 5 seconds of interaction to make a cup of coffee.
I don't use my Keurig any more, but its primary appeal was I could drop in a K-Cup, push start and walk away and then come back later to drink it.
It's all about priorities.
Folks do what they do because its good enough, and convenient. Which is a matter of taste, which I think might have been your actual point?