I agree, if money was the goal they would be better off doing like the Mormons, demanding a tithe and encouraging the members to get an education. I think money is important, but I think the power is even more important to them. Imagine being able to tell millions of people to do something, and not only do they do it, they think it was their own idea. That's power.
From the accounts I have read at Bethel, it is a very strange environment. Seniority is all powerful, getting you every thing from a better room to a more strategic seat at the table, which ensures you get first crack at the chicken. New people are ridiculed and harassed, power is used and abused. If you make it to the top of that dung heap, you are very powerful, the GB are Rock stars, big fish in that tiny pond.