"Don't pedestrians have to use the sidewalks?" asks a reader. The concern expressed here is that when a safe place is provided for pedestrians away from traffic flow, some people choose not to use it. The reader observes that these people make life difficult for drivers by adding one more hazard on the roadway.
First, a pause for thought. A highway is not the exclusive domain of drivers. It is a public way meant for all, pedestrians, cyclists and drivers. Over time rules have evolved to define how we share this community resource. When we follow these rules we know what to expect from each other in terms of how to share safely.
The term roadway is an important one to this discussion. The roadway is the part of a highway between the yellow center line and either the solid white line at the right edge of the pavement, or if there is no solid white line then the right hand edge of the pavement.