Green’s Dictionary of Slang

(US) one who picks up cigar or cigarette ends from the gutter or sidewalk.

1921		O.O. McIntyre New York Day by Day 25 Mar. [synd. col.] How pitiful those old men who walk along the curbs constantly watching the gutters. Cigar snipers, they call them.
1950		Goldin et al. DAUL 201/1: Sniper. A bum who picks up discarded cigar or cigarette butts.