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An extreme example of this would be Priceless Paperweight, when a really expensive/unique/etc. artefact is used for such mundane purposes.
Edit: on a meta-level, the whole idea of a "Doorstopper" is based on this: a book so big that it can be used as an actual doorstopper.
Edited by Florestan
^^ That's similar, though I was thinking more in the context of a Take That!, i.e. "The book isn't very good but it makes for a great coaster!" But I guess that fits that trope anyway.
I do some cleanup and then I enjoy shows you probably think are cringe.
This is something I see in comedies pretty frequently. An object, often a book, is not valued for its actual purpose but for some mundane purpose, usually as a coaster or to prop up a wobbly table or something.