Corrected entry: Frank, Archie, and Snowy are all rural boys from Western Australia but they all play Australian Rules football expertly. In 1915, Australian Rules was almost unknown outside of Melbourne, in New South Wales, the other side of Australia. In a time before television or film, they wouldn't even know what the ball looked like. The game only started to spread outside Victoria in the 1980s, and there is no way that three people from Western Australia would know how to play the game in 1915, let alone with such skill.
Correction: By 1901 football was the main winter sport in Western Australia. Fremantle rugby club in Western Australia changed to Australian Rules football in 1885. The West Australian Football League was well established by the time of World War I, and didn't even shut down during the war, unusually.
Correction: WA football has been around since before the 1900s - for example, South Fremantle Football club was established in 1900. This comment is factually WRONG.