Green’s Dictionary of Slang

goon n.3

also bag of goon, goonbag, gooner, gooneie bag, goonsack
[? mispron./abbr. SE flagon; or ? goom n.1 ]

(Aus.) a flagon of cheap wine.

[Aus]Sydney Morning Herald 13 Nov. 30: Tim Stanford started off drinking with ‘the goon.’ It’s a flagon of moselle or riesling [GAW4].
[Aus]Aus. Word Map [Internet] goon. cheap cask wine: We'd better get some goon for the girls [...] ‘Widely used in WA, also a ‘gooner’ or ‘goonbag’ is the silver bag the goon comes in’.
[Aus]Aus. Word Map [Internet] goonbag. Wine that comes in a cask: I had no money for decent wine last week so I bought a goonbag. Compare boxie, goonbox, goonsack. Also, goonie bag.
Littlest Zobo 27 Sept. [Internet] Goon! Goon is what Aussies call really cheap wine boxes.
Wikipedia [Internet] A box wine (also known as [...] goonbag, gooner, goonsack, bag of goon, or Chateau Cardboard).
stebo taeblog 3 Jan. [blog] We [...] finished an Abo’s handbag of red Goon (it’s a wine ‘product’ which means the over or under ripe grapes enhanced with sugar).
Skive Mag. Qly Mar. 12: Some youths were drinking from a big bag of goon, and another group of drunk young men were singing a Village People song out of tune.
[Aus]‘First Dog on the Moon’ in crikey, 2 July [Internet] The drinking is worse though, it is mainly about goon. Everyone drinks sacks and sacks of goon.
E. Shaw Thrill Seekers 73: We drank the goon straight in tumblers, in mugs with ice, blended into smoothies with apple and even banana.
[Aus] 2 July [Internet] Loves her Holdens, Collingwood football team and exposing her breasts. Enjoys drinking a goon sack of wine hung from a clothesline.