Might have something to do with this bloke: (courtesy of Wikipedia)

Ranogajec, according to insider accounts,[5] deployed, for his horse racing betting activities, a strategy combined of specific factors: identifying betting opportunities with as high liquidity as possible, meaning betting pools with significant money being bet by the regular gambling public; deploying a "highly sophisticated betting system"; identifying small margins, on which he bets significant amounts of money; and, importantly, closing deals with bookmakers, including industry leader TabCorp, for significant rebates on his bets. The latter has created controversy in the horse betting world, with many punters complaining about the alleged deal.[6] A TabCorp spokesman stated, in response to the media reports, that the corporation "investigated the incidents" and found "no evidence of illegal activity", but reminded the betting public that "the offering of tote-odds betting products by corporate bookmakers has inherent risks of pool manipulation [by large bettors]."[6]

Ranogajec reportedly accounts for 6-8% of Australian bookmaker TabCorp’s $10 billion annual revenue.[7] His betting on Betfair is believed to account for one third of the company's Australian operations.[8]

Ranogajec has gradually organised an extensive network of spotters, analysts, bettors and administrators, directing activities from office space he is allegedly occupying in the Fox Sports building at 235 Pyrmont Street,[9] in Sydney's inner suburb of Pyrmont.[10] It is known that he contracts many companies to provide information and does not employ anyone directly. However indirectly due to his information requirements, to gain the edge, he provides employment to over 300 people in Australia.[8]