Similar to Mallrats that hang all day in a mall..but these Wall Rats smell bad, usually don't have jobs, and dress like it is Halloween everyday.
Molly: "What! Why?"
Sally: "I forgot I need a cheese log for our Office meeting in the morning."
Molly: "You better remember to pack your mace to ward off the Wallrats."
"f that, im goin to wal-mart"
"dude you were there yesterday, stop being such a wall rat and come with us!"