Crosswalks in life

A road was recently expanded in my neighborhood, it is now a 6 lane road with a major intersection.To ensure maximum safety the city put up a new crosswalk together with a yield sign. A very good idea I thought as safety for pedestrians, bicycles and horses must be paramount. Yes horses! Can someone explain this one to me? I have heard the joke about the bear who goes into the bar and the chicken crossing the road but I have never heard the one about the horse waiting to cross the street.