The guys stay out late and they're also a mean bunch of pool players who can shoot a ball "straight" into the pocket almost every time.
The two words that begin these lines, "lurk" and "strike," make the boys sound like jungle cats or some other predator from a National Geographic nature series.
You could interpret these words as having sexual overtones, as young guys might "lurk" in places where they might see pretty girls walking past.
Their late-night habits could also suggest that they are involved in some shady business around town, although we should always be careful to not simply fall back on stereotypes of inner-city life when reading this poem.
The fact that they hang out "late" means they probably don't have regular jobs.
(Otherwise they would need to wake up early.)
They clearly have spent a lot of time practicing pool to develop that "straight" shot.