Illegal immigration is of major concern in Germany and in all European countries. Therefore we do of course try to send people back to their countries of origin--or, if possible, to the country of transit if readmission agreements are in force. Therefore there is a common effort, and it is one of the major tasks of immigration control to actually remove people illegally residing in Germany and the rest of the European Union.
As regards your second question, there are conditions to be met to be on this list. It effectively enforces the Geneva Convention on refugees and the European Convention on Human Rights in order to allow that this is constitutional. Our constitutional court has upheld the decision by the German Parliament to define such a list and to have such a list. Therefore, it has been established practice for more than 15 years.