The story
From crow + eater. Early settlers in South Australia were alleged to have eaten the breast meat of crows, parrots and cockatoos when there was a shortage of red meat. The term entered the lexicon in the late 1800s. (Alternatively, "crow" is a butcher's term for mesentery, an otherwise little-eaten tripe.)
Etymology from Wiktionary, CC BY-SA 4.0.