I enjoy both running and walking, at different times, in different situations.
At midday, when I just need to move, to get out of my chair and get my body revitalised, running is perfect. At times, I will even purposefully get in trouble in PE/Sports class, as the teacher's punishment is to make one run the perimeter of the PE field, or sometimes the stairs in the stadium. Wonderful exercise, really helps one to be able to sit through 3 more hours of boring lessons.
On the other hand, for enjoyment, I love trekking, hiking, walking. I love to feel the breeze and smell all the various things floating on that breeze, and to stop to smell and see all the little sights along the way. Sometimes I forget to walk, and just stop to enjoy something. These are things one misses while running.
So, I suppose running is for the exhilaration of movement, and walking is for enjoyment of one's surroundings. Both have equal value.