Do you not get that single-use disposable items are different than cars or phones that get used for years?
It isn't all or nothing, sure, but just b/c I still have a car (w/ great gas mileage that is 7 years old) doesn't mean I can't make a lot of other good choices.
Your "argument" just makes no sense. You are basically saying, we either need to be perfect or say screw it and do whatever we want, who cares about waste and impact.
Using Kcups is comparable to using paper towels, disposable diapers, paper napkins, individual water bottles, & plastic grocery bags not driving a car or having a phone.
Yes, they are very different, look into how those electronic devices are made. Look into the energy used to produce the materials they are made with. There is more to being eco-friendly than not filling up our landfills, so the comparison between those items and K-cups is valid. Ironically, I would expect someone who was so concerned to actually know that.