As I review PhD positions available in my field (environmental engineering/sciences), it seems to me that some subjects are simply big case studies. I mean that the entire research is about applying an existing method to a new place or context rather than developing a new method.
Of course, since no place is truly unique, the method will have to be adapted to it and this might lead to a significant contribution to research. But still it leaves me with the open question of what is the benefit of such a PhD for the student's future career?
I would guess that doing a PhD on a case study rather than on fundamental research leads to better job perspective outside academia, for example as a consultant, but that might hinder your chances of doing an academic career. The problem is that with a BSc or MSc you can already do consulting, so such a PhD seems pretty useless. But maybe I'm missing something of the big picture, hence my question here
Finally, are such PhD offers common in academia in general or limited to some fields/geographical areas?