How does Shakespeare appeal to the groundlings in the first scene and what was his purpose in doing so?

The opening scene is full of puns and comedy that quickly disappear from the play. This would engage the groundlings and prepare them for the more heightened themes that follow. Also, this scene is one of the few almost solely devoted to common characters in the play, and they are excited about Caeasar's return to Rome. Perhaps Shakespeare is giving the groundlings something to relate to and to prepare themselves for the arrival of the titular character in the same way.