Possibly it TAXES, they are scared they may have to pay their share and if they do, they will call it persecution.
Armageddon to the WTS, maybe?
Amplifying on buff's thought:
I recollect that Rutherford declared something on the order of "OK 2 pay them, but not one cent we don't have to" about taxes; then Knorr came in, doing a McNamara style reorg/streamlining/. I think they discovered the "non-profit org" scenario about then. They've gotten real used to it. You can make a very nice "money engine" if you qualify on that one.
Yeah, they would choke if that rug got pulled out from under them. That's why they started doing bizarre things like the amicus curiae for the California preacher getting taxed.
On that score, the late Dr. Gene Scott (Assemblies of God) had been fighting similar battles for a long time. But he took the other tack: his Dolores Press PAYS the taxes. Those books are pricey; but they are often unique intellectual items.
What about that whopping 60% tax thing in France? In the US, you couldn't pull that; but under Napoleanic Codes the state trumps whatever it likes. Don't know how that will turn out...
As some wag once said "follow the money"...
Mustang