I understand the arguments about freedom of speach...but I don't see a problem to having to get some kind of permit to go door to door. You have to get a permit to drive, permit to build something on your property, etc, etc...
I wouldn't have a problem if the watchtower needed to pay a permit fee for ea witness going door to door...say $10 per year, per pub in the US. Would we all like to see the WTS have to shell out 10mil.