Has a doctoral degree any value outside of its main area? The phd area is Computer Science and the other area can be anything - if this info makes any difference...

I am asking from the practical point of view, specially something that can be evidenced by real examples. Some career that requires/rewards the degree despite of being completely outside its scope would be a good example.

I was worried about asking something a little open, but I see it is pretty common by here, e.g. - the opposite of other more harsh communities.
Though the topic of your dissertation may be extremely narrow and focused, the process of acquiring a PhD teaches you the skills to attack virtually any problem very deeply, if given sufficient time.  Ultimately, the PhD is just a piece of paper.  The real value of it is the ability to produce something of value to others (i.e. research, a product, etc...).