I'm definitely seeing a lot of people who simply aren't able to divorce what they know about the walkers with what the characters know about the walkers. The characters don't know what's going on. They obviously have encountered enough of the walkers to have an inkling of what's going on, that "you get sick, you die, then you come back and attack people."
This family is a microcosm displaying the breakdown of society. It might not be the full "let's watch a city disintegrate" that some people are looking for, it is consistent with how the show handles these types of things. That is, rather than the grand (and yes, expensive) perspective, they take a small set of people and show how they react/survive in this situation.
But let's take a real life situation (for those of you struggling with "but these characters are stupid!"). Remember the big tsunami in Indonesia in 2004? When the waves receded from the beach, how many people actually went toward the water? Thousands of them. We can sit here in hindsight and say "didn't they know that was a sign of a tsunami and they should be running in the opposite direction?" No, they didn't. They went toward something odd to see what was happening.
So try to take that perspective here. These characters aren't stupid: they simply don't know what is happening and are piecing it together.
I disagree. That tsunami analogy is rather poor. I'd argue that most that do not live on islands have no idea what receding tide means. I think everyone can realize what a snarling human trying to eat your face or eating your neighbors is. Someone either a) on bath salts or b) a zombie. Even if zombies as we know them don't exist in that universe's pop culture, after you see one up close in real life, some gears should start turning in your head. These characters are absolutely stupid, like every horror character that isn't written to be a guide.