Would you rather have the bulk of your play's action staged in the atrium or in the peristylium? That's not the question, actually.
The difference between a movie and a stage play is entrances and exits. In a screenplay, you don't have to bother with any of it: you simply introduce a new shot and go on with the story.
On the stage, you have two exits: stage-left and stage-right. Three, if you want to push it and make your play difficult to produce.
Now. There's a room (the living room of a house) with two exits: one on the left, the other on the right. The house is huge. The left-hand exit leads to the garden. The right-hand exit leads to a whole bunch of passageways, stairs, rooms, etc.
When a character exits stage-right, and another one comes in twenty seconds later, the audience MUST NOT get the impression that they just ran into each other. How would you accomplish that?