How did they survive in a hospital in overrun bombed out Atlanta for years?

How is the cast even still close to Atlanta after all the traveling they've done? Do they just wander in circles which happen to have these weird communities full of smurfed up morons in close proximity to each other?

How did Beth make perfect head shots in the dark shooting one handed with a bandaged hand?

How did a guy with a limp manage to walk right through a pack of zombies unscathed?

Mysteries of the universe.