I remember these too, beginning in the '70's. Everythng was geared as a frenetic rush.
We'd go to the homes and knock---no sermon or anything, and tell the householder, "This important bible message is being given worldwide at this time. (hand them the tract). This is your personal copy."
And then we were instucted to leave. NO discussion. No nothing. As Blondie said we were each assigned 100 and they had to be distibuted within 10 days! Then they went to the 'no talking" method. Just place your 100 copies. It did appear that the "end" was coming swiftly and that we were so priveleged to be able to be a part of that warning of impending (soon, mind you) destruction about to come upon mankind. No wonder our friends and relatives thought we were looney! We were!
By the time the '90's rolled around, this urgent and important message had lost its shine and this kind of campaign got to be humdrum. You can only summon up that kind of enthusiasm when there is truly something to be enthused about!
Annie