Not every crosswalk. This is explictly only for signaled intersections/crosswalks. i.e. those that already have a pushbutton, a walk sign, and a stoplight. Tha

Not every crosswalk. This is explictly only for signaled intersections/crosswalks. i.e. those that already have a pushbutton, a walk sign, and a stoplight. That only covers a very small portion of crosswalks and is generally done for crosswalks in high throughput areas or areas where risks of a pedestrian/vehicle collision are high. i.e. the places where you'd want additional augmentation to notify drivers and prevent collisions