There was a Simpsons episode where a pair of JWs knocked, Marge didn't get to the door in time, they left and had a conversation with each other to the effect of "why are we wasting our lives? we don't have all the answers", after which they tossed the WT mags in the trash at the end of the driveway. Marge was lonely, and so disappointed that they left she said "I would have feigned interest"...
Then there was a really funny scene in the Coneheads movie, wherein the Immigration agents trying to track them down knocked on the Coneheads' door posing as JWs; they were very convincing (even though they got a couple details of JW eschatology a bit "wrong").