May be it will be revealed in the game story line. You're not giving him a chance. So far the biggest reason you've given for hating Skarblitz is because he has Hatred and Preferred Enemy (Space Wolves). So do you hate every Warboss that has looted Space Marine bitz? Because Bosspoles without Space Marine helmets are rare indeed. Any Nob worth his teef has at least two or three displayed somewhere on his person.