How might Zaroff find men to hunt?

Zaroff says

"I hunt the scum of the earth sailors from tramp ships—Lascars, blacks, Chinese, whites, mongrels—a thoroughbred horse or hound is worth more than a score of them.''

From this statement, I would infer that he makes periodic trips to the docks of large ports and hires sailors which he then brings back to his island and hunts.  The story was written in the 1920's and Zaroff has many of the poor stereotypes of immigrants common in America at the time.  He would think nothing of enticing these "scum" sailors to his island on false premises for his hunting pleasure.