Some of the other modern commentators have noticed that the 'herms' could have been a form of gibbet for crucifixion/impalement. The ancient Greek images (on pottery?) would show something like a wooden or stone crossbar, going through the herm at the shoulder level. The commentators noted that the crossbars might have been for more than draping garlands of flowers. Arms over the crossbars (for crucifixion); impalement on the stone (or wood?) phallus. One of the commentators started to research what the Greeks used the for. Had some quotes describing them used (sometimes) for punishments.
Yeah, DeMille knew what he was showing/implying. Most of the pop culture illustrations in the 1920s & 30s would show a herm without an erect phallus. If a person was well-educated they would know what an actual herm would have had on the sculpture.