The Synod of the CRCNA in 1928 issued a declaration regarding "worldly amusements," warning particularly against theater attendance, dancing, and card playing. I just looked at this thread and did not see that sort of thing referenced that you might be interested in from a 20th century source.
And then, of course, there was the whole situation with the assassination of President Lincoln. More than a few, clergy and lay, were critical that the President was in attendance at the theater when he was shot. Likewise, no small part of the impetus to moving him (there's an argument about whether he could have better been treated there in the Ford Theater) was that a variety of folk were determined that the President of the United States would not die on the floor of a theater (or anywhere else in such a place).
And reflecting the sermon by Samuel Miller, Charles Hodge, when he was on his two-year European tour (1826-28), had many opportunities for "cultural enrichment." He availed himself on more than one occasion of concert-going but steadfastly resisted all invitations to the theater.
Peace,
Alan