Lighter: I can't imagine anybody considering movie music a "commercial recording" until the days (in the '50s, I believe) when soundtracks of movie musicals began appearing on discs.

Bob: To clarify: I was curious about recordings of performances made specifically for sale to the general public rather than issues of 'field recordings' such as the early Library of Congress sets.

Was there was ever much of a cinema shanty genre?

Just for discography's sake, “Talkies” came after silent film. If the score wasn't a live orchestra or monstrous theater organ; it was a phonograph. Moses Asch (Folkways) got his start wiring older New York venues for sound. Dubbed bootleg 78rpm Soviet movie scores were Stinson Trading Co.'s stock in trade until the Asch era.

Also, studio, field or on location, most anything recorded before that 1950's long play vinyl will be unnaturally short in duration. The modern pausarius is always just off stage with his three minute stopwatch. Calypso road marches; Gregorian chants; pump shanties; opera & decent jazz are all off the program.