I believe that you are wrong here and misleading. You are almost saying that royal families don't train their children to acquire some knowledge and skills to equip them in the society.

On the other side of what you are saying, I have to remind you that royal family members were those who held very important positions in the society and if they don't have skills, they won't be able to fit in. Children of Royal families historically were the best educated, they go to high level schools to prepare them for leadership and government offices, diplomacy and society ethics. They equip themselves in the study of different languages, arts and culture of their society, craft, business and management skills. They also study professional studies like medicine and law etc. Those are skills for the royal families which the middle class find it difficult to attain.