I guess I'm in the same situation as you, TS, although I never considered the idea that I'm "registered" for anything.
I've had no contact with "the church" in like 20 years...are they really still keeping my name on their "list?"
I would be curious to learn more about the subsidies and benefits you say they're getting based on these registration lists, how they keep them current, how difficult it really is to get off them, and if the things you're saying hold true in the US. I may do some googling. I'm almost positive I wouldn't get a visit from a priest if I tried to get off it.