I personally believe that most of the higher ups at Bethel are simply delusional true believers and are just naively following the public example and teachings set by the conmen who came before them. I don't really see any individual or group who reflect Rutherford in his building of Beth-Sarim.
So, as far as I know, I don't have much reason to doubt that the majority of the money has gone back into either building projects, writing and distributing their literature, and supporting missionaries. However, those are all a waste of money in my opinion since all they do is promote a narrow-minded and in some ways dangerous ideology.
Once again though, most of the dangerous and controlling aspects of the organization where simply inherited by the people who run it today and they are just trying to rationalize it because they truly believe it be God's will.