The USA tax exemption has ramifications far beyond simply "avoiding taxes." It's used in "PR," to influence others, including other governments, used to somehow authenticate Scientology as a "Church," and as a "Church," Scientology becomes exempt from myriad other restrictions and scrutiny that would be imposed on any other individual, corporation, business, etc.
Also, re-examining the tactics used by Scientology, in its "war" with the American IRS - aside from the more obvious and notable (and likely, but not proven, such as blackmail) tactics used to overwhelm - other more "subtle" tactics include Scientology 1) making itself not understandable to the IRS, and 2) (falsely) assigning significances: two things that Scientology does to Scientologists who are encouraged to read "all" of "LRH," while prevented from reading all of LRH (with the all influencing Scientologists, even though it's unknown to Scientologists; and as for "assigning significances," well, there's "Your meter will tell you," and "This is the cold blooded and factual account of your last 60 trillion years," and "The whole agonized future of this planet, every Man, Woman, and Child on it," and then the advertized confidential part of Scientology: the (enigmatic, yet vital to your and Mankind's survival) "Implantology" levels of the Grade Chart.
Then comes the part of Scientology that is secret but not advertized, and if you're a typical Scientologist, you'll have no idea whatsoever about that part, but, if your "needle is floating," you'll be expected not to care.
Yet, the not-advertized secret part of Scientology, which includes tactics that Scientology used/uses on outsiders to "handle" them, is revealing as to what Scientology (internally) does to Scientologists. These tactics (internalized) and used on Scientologists, were built into Scientology's multi-layered publicized, publicized secret, and secret secret doctrine by its founder.
Quite a trick.