“losing the sink as a consumer”

Can anyone please explain the meaning of “losing the sink as a consumer” at the end of the paragraph below?

This would be the first time American coffee consumption dropped in several years, and naturally provoked a reaction in the press, with many attributing the decrease to the rapidly increasing popularity of single-serve, or “pod”, coffee machines. The theory is that single-serve machines reduce the amount of waste involved in making coffee, thereby “losing the sink as a consumer.”

The idea suggested here is that of the kitchen sink swallowing coffee. A large proportion of the coffee made, but ultimately not drunk up by the consumer, used to end up in the sink (or down the drain).

Thank you Susanne!!! It’s now all clear to me. Until I read your comment, I could not see a “sink” as a consumer. Now it all makes sense.
Thanks a lot!

You are welcome. (Your reply gave me a chance to insert ‘to’ into my original response … I so dislike my careless mistakes!)