I dug up some information on this subject and will briefly type the just of what I have found out and have in my file.
"We never solicit donations," WT Society says, on page 27 of the book Jehovah's Witnesses in the Divine Purpose, quoting from the WT magazine , Jan/Feb, 1882,p.2
State of California informs Jimmy Swaggart Ministries that tax is due for religious books and tapes sold in the state since 1974. Swaggart eventually pays the tax-$183,000.00-but sues for a refund.
Jimmy Swaggart confesses he had commited a "moral sin," reportedly consorting with a prostitute.
WT Society distributes Feb, 1989 issue of OUR KINGDOM MINISTRY, declaring that JWs are not "agents or representatives of the WTBTS." Page 3
The article mentions the possibility of "an accident" on private property while distributing literature.
U.S. Supreme Court rules that it is illegal for the state of Texas to exempt religious books from sales tax. This strikes down such exemptions in 15 states. Other states with sales taxes had been taxing religious books all along.
WT Society gives away "free" new books released at U.S. conventions, abandoning the long-standing practice of selling the books. Witnesses are instructed to place donations in contribution boxes to cover the cost.
JUNE 22, 1989
WT SWociety files "friends of the court" briefs including National Council of Churches and Society for Krishna Consciousness.
JANUARY 17, 1990
U.S. Supreme Court rules against Jimmy Swaggart Ministries, declaring that the sales tax must be paid.
FEBRUARY 9, 1990
WT Society writes letter to congregations announcing that literature will no longer be sold to JWs at the Kingdom Hall, and that no price will be set when JWs distribute materials door-todoor.
FEBRUARY 25, 1990
February 9th letter from WT Society is read at Sunday meetings of Jehovah's Witnesses across U.S.
MARCH 1, 1990
New policy of distributing literature without naming price goes into effect.
MARCH 11, 1990
Announcement is made at KHs in U.S. that food will be available at no cost, on a freewill donation basis, at J.W. conventions.
[The March 15, 1990, WT magazine and March 22nd AWAKE!-printed earlier-still say"25 cents(U.S.) a copy" and "$5.00(U.S.) per year." The April, 1990, Watchtower no longer carries a price]
The thing I find ironic about all of this is that the April 1, 1990 Watctower on page 20 says concerning Jehovah's Witnesses: They do not dodge taxes or seek to evade inconvenient laws.
Also in 1991 the WTBTS annual sales totaled more than $1,248,000,000.00 up nearly $1/4 billion from just over $1 billion in 1990 according to readers wit access to computer-linked credit reporting services.
Just think of the whopping tax the WTBTS would have to pay if they stayed with pricing literature. Free will donations for literature cannot be taxed because of no set amount.
Hope this info helps.