Another grand stretch for the sake of trying to make a point where none exists.
What does it cost to keep a mature well, typical to Hemi's mature wells, in SE Kansas? Without the answer to that question, one cannot accurately say that there's a "high cost of production" for the typical Hemi mature well.
Then there's that persistant context issue again. The process of taking offline non-productive wells AND bringing online pre-existing/refurbished mature wells is an ongoing process that is constantly occurring. I'm pretty sure the context Hemi is presenting via their website is just that... demonstrating both an efficient operation by having enough existing wells to keep a relatively steady pace by taking out the non-productive, but also introducing other productive mature wells.