Interesting quandary.  As a loose analogy, isn't this roughly equivalent to what commercial banks do?  They hold the funds, then use that value to generate additional value?  It's not like they seek permission from you about how they use that wealth.  Maybe you earn some interest in the process, but when you eventually withdraw your funds, the bank do keep the profits they made from the value they generated from you.  

I can see why some people aren't exactly comfortable with someone operating that particular business model when it comes to forum funds, but there was clearly no rule against it.  Depending on your personal stance, the opportunism is either admirable or sickening, heh.

While mob rule is obviously too tempting to resist for some, I'm going to stay on the fence and say that it's ultimately a matter for theymos and OgNasty to work out between themselves.