I know it used to be the practice of radio stations to play the National Anthem at sign-off. There still is a large number of stations that sign off at midnight or thereabouts (particularly those in small markets). I wonder if they still do...I wouldn't know since I'm in the rack long before then.
I know in Houston, KIKK 650 AM used to sign off, which is now the station that airs Howard Stern. I am very surprised no one has called that bias to air the American Anthem among the leftist.