riffraff

crud, sewage, slop, swill, wash

detritus, remains, rubble, ruins

dump, scrap heap

lumber, odds and ends, trumpery

flotsam, jetsam, wreckage

castoff, cull, discard, hand-me-down, reject, throwaway

dregs

commoners, commons, herd, hoi polloi, masses, millions, mob, multitude, people, plebeians, populace, public, rank and file

bourgeoisie, middle class, working class