Swag has a real, documented upside — it is not a wasted line item. But it is also not a traffic driver on its own: a table of pens and stress balls does not make anyone slow down who was not already stopping. It rewards people after they arrive; it does not pull them in.
If your booth budget is entirely swag, you are spending on retention with nothing spent on acquisition. This guide covers traffic ideas that create the pull swag can't, and where swag still earns its place once people are already at your booth.