What does "cockney slang for a crowd" mean in the etymology explanation of scrounage?

"to acquire by irregular means," 1915, alteration of dialectal scrunge "to search stealthily, rummage, pilfer" (1909), of uncertain origin, perhaps from dial. scringe "to pry about." Popularized by the military in World War I. Perhaps related to scrouge, scrooge "push, jostle" (1755, Cockney slang for "a crowd"), probably suggestive of screw, squeeze.