Green’s Dictionary of Slang

(US) a thief who specializes in robbing shop tills.

1834		Sthn Reporter (Cork) 8 Mar. 4/2: The Old bailey calendar abounds with the trials of boy lob sneaks, but no men.
1859		Matsell Vocabulum 52: lobsneak A fellow that robs money-drawers.
1887		J.W. Horsley Jottings from Jail 24: Poor old Jim, the lob crawler, fell from the Racker and got pinched.
1894		A. Morrison Tales of Mean Streets (1983) 150: Scuddy went regularly into business as a lob-crawler: that is to say, he returned to his first love, the till [...] to be approached in unattended shops by stealthy grovelling on the belly.
1895		C. Crowe Aus. Sl. Dict. 46: Lob Sneak, a fellow robbing tills.
1896		A. Morrison Child of the Jago (1982) 161: Josh was to take his trial [...] at the Old Bailey, and not at mere County Sessions at Clerkenwell, like a simple lob-crawler or peter-claimer.
1937		E. Raymond Marsh 126: Why, there’s kids here that go nickin’. Real proper little lob-crawlers they are.