The impression I got was that aristocratic breeding was tightly controlled by the Bene Gesserit. And as for Caladan- what could they possibly do? If they tried to rebel against the new Dukes, they'd be stomped on by the Sardicar. If they tried to go intergalactic- the Guild would refuse to transport them.

The impression I got was that aristocratic breeding was tightly controlled by the Bene Gesserit. And as for Caladan- what could they possibly do? If they tried to rebel against the new Dukes, they'd be stomped on by the Sardaukar. If they tried to go intergalactic- the Guild would refuse to transport them.