The carrot and the stick - but which one sticks?

.... Any civic campaign is always a problem - should we use a funny, upbeat message (i.e. the carrot) or should we go directly with the fear and punishment element (i.e. the stick)? In the case of these ads by the Ministry of Interior it was the former that was used. The first says "It is not allowed to throw liability under garbage" which is the reverse of the usual warning in Arabic, the second says "not a tasty treat" which is a double-entendre in Arabic for something that is not tasty but also for a situation that might not be too funny. There is high speculation that the second came as a retaliation for Nando's "Ma tekol zabet, kol Nando's" (Do not eat/get a parking ticket, eat/get a Nando's) which was previously commented upon in Beirut/NTSC all while noting that Nando's did some creative media of parking tickets which were actually invites to go eat there. The third says "Our hand is in your belt" which is a local expression used when someone is expressing trust in someone else, naturally the "belt" in question is the seat belt. So, if the campaign is so witty and funny, why am I expressing some reservations? Because, in the words of a taxi driver who was not wearing a seat belt and a I casually mentioned the billboard with the ad sitting right on top of his head: "This is cute. But this won't entice me to wear it! Where's the threat?"... Yes, where's the threat in a funny, but foregetable campaign (Which did win the Pikasso d'Or of this year - and rightfully, if judged solely on its creative campaign).