This reminds me of how book stores "return" unsold books to the publisher:
Shipping boxes of heavy books costs a lot of money, and the publisher doesn't actually need the books back (because they can always print new copies very cheaply).
So the publisher just tells the book store to destroy the books, and as evidence for their destruction asks only for the covers to be shipped back to them (which is cheap).
This is why books contain within them the text "This book should not be sold without a cover".
So with this printer company, they are effectively "destroying" the unused ink cartridge since it's not worth it economically to have it shipped back to them.
The added bonus is that if the customer renews the subscription then the ink can be "undestroyed"!
Shipping boxes of heavy books costs a lot of money, and the publisher doesn't actually need the books back (because they can always print new copies very cheaply).
So the publisher just tells the book store to destroy the books, and as evidence for their destruction asks only for the covers to be shipped back to them (which is cheap).
This is why books contain within them the text "This book should not be sold without a cover".
So with this printer company, they are effectively "destroying" the unused ink cartridge since it's not worth it economically to have it shipped back to them.
The added bonus is that if the customer renews the subscription then the ink can be "undestroyed"!