Being out late was probably not in Luke's best interests, but since he couldn't sleep, he'd spend his time exploring the city instead. He accidently got turned around at some point but instead of admitting that he's lost, he's surveying some of the closed shops and taking note of them for future reference.

"Okay, what street am I on now...?"

He continues wandering around with no real direction in mind while mumbling to himself, completely unaware that there's a Batgirl not too far away from him.