2. The case being made for remaining in safe and perfectly defensible locations
The problem with every zombie virus film is that it needs a dramatic finale. In real-life if you found somewhere full of food and free of death, youd put your feet up and wait out the rest of the apocalypse. But movies are not real life. Movies need climaxes. They need closure. So we end up with someone suggesting: Hey, lets leave this safe and secure building and... make for the coast! Its always the coast. Maybe they somehow know zombies cant swim. Anyway, we then get a Dawn of the Dead-style denouement where everyone dies, and the surviving survivors realised they should have just stayed behind. Even though they knew that anyway.