I’m sure there were commercials. Back in the 1970’s the commercials were for free Bibles (with LDS footnotes) and Books of Mormon. You called then the Missionaries would come over to visit.
Why is it that SLC headquarters NEVER asks you to 'pray' about the truthfullness of the Book of ABRAHAM?
It, too, is MORMON scripture.
Why no asking for a sign about the voluminous Doctrines and Covenants?