Membership numbers are accurate.
Active membership is different from total membership.
Anyone who is baptised into the church, is not dead and has not requested removal of membership record is counted.
The business side of the church does indeed exist, it's pretty difficult to miss. However, it is completely separate from the ecclesiastical side. Nothing wrong with that. If they aren't required by law to open their books, then oh well. Doesn't really matter, does it?
Wanna know how much money the church has? 10's of billions. Happy?