Green’s Dictionary of Slang

a general term of abuse, also attrib.

1942		H. Miller Roofs of Paris (1983) 236: I’m a bastard, she says, a son of a bitch, uncle to a family of shit-eaters.
1952		E. Hemingway letter 2 Oct. in Baker Sel. Letters (1981) 785: When I was a boy some one told me that we had to eat a ton of it in our lives [...] But sometimes I react a little and say, ‘I am very sorry, gentlemen, but I am not hungry today.’ Confirmed, or patriotic, shit eaters never forgive this deviation.
1971		B. Malamud Tenants (1972) 123: I told you not to let this redneck shiteater come along here.
1982		S. King Running Man in Bachman Books (1995) 576: I’m laughing at you shiteaters.
1996		(ref. to 1788) Sydney Morn. Herald 29 June 145/3: Aborigines [...] mocked the Europeans for their clumsinbess and stupidity [...] called them ‘gonin-patta’ — shit-eaters.
1987		Age (Melbourne) 7 Nov. 16/2: ‘You stinky little shit-eater’.
1999		T. Parker South Park: Bigger, Longer and Uncut [film script] Listen, you donkey-raping shiteater!
2012		Chicago Trib. ‘The Onion’ 1 Nov. TAB-5/2: Those shit-eaters are [...] completely chemo-resistant .
2023		(con. 1962) J. Ellroy Enchanters 321: [H]e cracked a shit-eater grin.