Turner Classic Movies often runs "prestige" films (e.g., My Fair Lady, Lawrence of Arabia, Doctor Zhivago) with an overture, intermission, entr'acte, and exit music. They don't make these up, so they're presumably part of the actual release materials. However, they always provide their own screen graphic. (A blank screen might lead a viewer to think that his reception or his set has failed.) All of this suggests that these were audio-only for theatrical runs.
Indeed, as I said upthread, overtures were to be music only in the theater, because the curtains were closed. The graphics we typically see (on the older releases anyway, newer blurays eschew the graphics in favor for black screens with a simple title on it) have been added by Warner Bros., Sony, etc for the home video release. The graphic wasn't added by TCM, they just play what they're given when they license the films to air.