Rick Grimes: This is how we survive. We tell ourselves that we are the walking dead.
Carol: haven't had a chance to say, I'm glad you came back.
Daryl: To what? All this?
Carol: This is our home.
Daryl: This is a tomb.
Carol: That's what T-Dog called it, thought he was right, until you found me. He's your brother, but he's not good for you. Don't let him bring you down. After all look how far you've come.
Rick: It is pretty stupid for us to go out there, right?
Daryl: Yep... do it again tomorrow?
Rick: Yep.
Gabriel Stokes: What you're saying... doesn't make you a sinner. But it does make you a tremendous shit.
Answer: Walkers are attracted to noise, they can tell who's dead and who isn't dead, in S1 when Rick and Glenn cover themselves in walkers' guts they're able to get far by walking through the herd of walkers because they smell like they're dead, but as soon as the guts get washed off by the rain the walkers immediately attack them, if you draw attention to yourself they will attack you which we've seen that many times throughout the series that it's not always successful. Whether you're covered in guts hiding under dead corpses or under a car.