Green’s Dictionary of Slang

(Irish) a useless person.

[1852		Freeman’s Jrnl 8 Sept. 4/2: The great amount of mischief done by a class of men known as ‘gather-’em-ups’, who are in the habit of vending all kinds of trash to children in barter for what they induced them to steal from their parents].
1979		M. O’Beirne Mister, A Dublin Childhood 82: ‘That oul gather-em-up,’ mother said in disgust. ‘With his bike and his blarney’ .