Hence you better have something that will attract them from mid-aisle. A simple statement of the benefits of using you. Your differentiation strategy. Also, you should plan ahead and schedule appointments before the show. Appointments at your booth are prospects.
Folks walking by are suspects.
When there are no prospects at the booth, or one of the sales folks are not busy they must go into the aisle and drag people in. But, we paid to be there, and we need the business. I don't believe in the magic shows, card tricks, etc to attract an audience. I started the speakers at a booth many years ago. We had an 8x8 booth in a 10x20 space.