Some streets in Pompeii can't possibly have held any but pedestrian traffic. Notice the residents still required a deep trough to let water flow down; the detail in the elevated side walk is entrancing.
At some houses and businesses, stone benches and perhaps awnings afforded a resting place for visitors or passersby. It's hard to know exactly--no awnings survived the eruptions.
Beard, Mary. 2008. The Fires of Vesuvius: Pompeii Lost and Found. Harvard University Press, Cambridge.