What do you mean "shoot the vic"? Shoot Lizzie in the leg? Cruelly let her bleed to death then turn? If she doesn't die someone could find her, nurse her back to health and then crazy Lizzie kills someone else? We saw what her mind made her capable of. We know the world they now exist in. There's no logic (or just…

They knew and loved both Lizzie and Mika and the walker on the tracks was nothing to them, simply a no-legged walker. Why would they waste their time going over to it and "killing" it? By that logic they should roam the countryside seeking out walkers to neutralise.There's no inconsistency at all.