How does Max Brooks use imagery in The Zombie Survival Guide?

Imagery:

"Of all the weapons discussed in this book, nothing is more important than your primary firearm. Keep it cleaned, keep it oiled, keep it loaded, keep it close. With a cool head, steady hand, and plenty of ammunition, one human is more than a match for an army of zombies."

"Buildings in poorer, inner-city neighborhoods tend to be more secure than others. Their reliance on high fences, razor wire, barred windows, and other anti-crime features make them readily defensible. Buildings in middle- or high-income areas tend to emphasize aesthetics. What rich city council wants an eyesore in its neighborhood? Instead of ugly, even tacky, safety features, these affluent people rely more heavily on law enforcement and private security (forces of proven unreliability)."