Auschwitz is not really a huge amusement park. There is an incredible amount of research that is being conducted at this institution daily. The camp provides a means to study organisms in controlled settings which is really important for scientific work. There are studies that must be done in society, but there are other studies that can be done in a camp, reducing cost and time.

Humans are a fascinating species, and so it makes sense that we want to study them more. The first step in doing that is bringing them to a camp, but before that can be done you must be able to keep them alive. All of this amounts to very important research. Think, for example, what was learned in the studies on "why are they dying" and what came of it - specialized trains, new methods, etc. All of that was because we wanted to put them in a camp.

TL;DR: research occurs at concentration camps, but you need to figure out how to keep your animals alive, first.