For some horses become a hobby once you have earned money, so you are satisfied economically.
So perhaps he is using pillars of hope as a kind of stud farm. So the children are just cheap labor to prevent the facility from falling apart.
Yes, there are seminars and computer classes, but the main reason for them being there is properly the chores aka manual work, they are doing there.
The facility seemed runned down and the lack of detainees on the campus could be that there are few or the more critical ones were hidden somewhere out of the camera locations.
How many detainees are there today?