Green’s Dictionary of Slang

1. a thief.

1841		Bell’s Life in London 22 Apr. 4/5: In the scuffle the ‘gleaners’ were again at work, picking up stray purses and watches.
1890–1904		Farmer & Henley Sl. and Its Analogues.

2. in weak use, a sponger.

1926

O.O. McIntyre New York Day by Day 7 Mar. [synd. col.] He became a gleaner and a wastrel along the way that is white.