I think the ability to cast far is important. Even though most fish aren't caught that far out, if an angler is casting into the wind a seventy-foot cast becomes and fifty-foot cast. Also, an angler who uses good casting technique will not get as tired as fast as one who doesn't.
In the end, however, for me, long-distance casting is about overcoming obstacles and defects, and coming in-line with an ideal that can't be seen. For me that's the spiritual side of casting.
After four years of practicing and experimenting with long-distance fly casting techniques, I was able to cast over a hundred feet. (Even though I read everything I could about casting, in the end I had to find my own way.)
The Fly And Spin Casting Site