People get something out of being in this cult though don't they? Very ordinary, uneducated people get to be ministers preaching in a church setting with congregations forced to listen to them even if it's drivel.
Positions of authority with a huge amount of control over people's lives. They can drag people into JCs and make them spill their guts about intimate sexual encounters. Even throw them out, forcing congregation members and their own family to shun them. It's too much power for the average uneducated man in the street to cope with without becoming corrupt.
This religion should fail but the pay off is too tempting for some. The GB knew exactly what they were doing when they introduced the elder arrangement.