In every city, there are places where you could rig up a trapdoor setup, like off a bridge or overpass, where you could bait zombies to "walk the plank" off a ledge where they would be killed, or their legs broken by the fall. Would a zombie figure out that every other zombie is falling to their doom? Or would they just keep trying for the bait and go off the cliff like herd of lemmings?
First of all, they're already dead so falling off a bridge wouldn't kill them again. And if their legs weren't broken, they would just get up and keep on truckin'.
And just how exactly would that perpetuate the continuation of this series, assuming of course that your idea had even an iota of being successful?