Green’s Dictionary of Slang

greasy n.²

a shearer.

1939		Bulletin (Sydney) 14 June 20/1: When the mob lined up [...] the greasies found that one of the two learners was a cocksure little beggar [AND].
1943		Bulletin (Sydney) 3 Nov. 12/1: A bunch of greasies downed handpieces in a Longreach shed.
1956		F.B. Vickers First Place to the Stranger 134: When those five greasies get moving they’ll shear a lot of sheep.
2003		McGill Reed Dict. of N.Z. Sl. 93: greasy A butcher, shearer, rural cook or fastfood cook. ANZ C20.