Usage and Grammar

Q. From your July Q&A: “Comprehensive tip sheets for setting up a paper are available for free at the Turabian.org website.” Really? “For free”? Free here is an adverb modifying the verbal phrase “are available,” not a noun, and cannot be the object of the preposition for.

A. Uh-oh. Somebody had better tell Merriam-Webster!

[This answer relies on the 17th edition of CMOS (2017) unless otherwise noted.]