The entire practice of photography is about light. All the way from the ancient camera obscura to the wet plates of the first real cameras during the early 1800s to the light field technology from Lytro today, everything revolves around observing and, with the advent of the wet plate, capturing the light.
Even the modern day digital manipulation of photos primarily concerns itself with bending the light to more closely match the vision for the photo. Even minor changes can have substantial differences. Above is a photo of aspens with some of my normal technique and below I've taken a very similar shot (captured within an hour or so of the other) and softened the light a bit, but it was more than enough to give it an almost painterly feel.
Of course, photographers will always follow the sun. The crowd in the photo below walked a mile and a half to see and photograph Delicate Arch at sunset.
But it's all worth it when the light does things like this.
The seemingly magical light shortly before sunset and after sunrise is even termed "golden hour" for the glow that it imparts to pretty much any photo. There's a good reason all those photographers were crowded around waiting for sunset and not noon.
