Your arguments are flawed. I don’t have to accept raiding as moral for my arguments to be true. For example, many Americans followed a strict moral code, inspired by and based on the Bible, while happily owning slaves and hanging non-white people from trees if they dared to object to being slaves. A clear example of in-group morals and non-morals directed at an out-group. I am sure those slave owners had a strong sense of justice and fairness to people in their own group but none towards other groups. Exactly like the Vikings.