In the dim & distant past, before the ex-PMG telephone division trading as Telstra was privatised, it was run into the ground by the CEO, a shifty prick called Sol Truillo & his assorted American cronies. One of those cronies, Phil Something-or-other had recently (at the time) earned a doctorate in some business-related field.
This is where he came upon the Aussie tendency to think of a doctor as purely one of the medical or dental fraternity. Out here, you may well be entitled to refer to yourself as Dr So-and-so, but it's not something general society comes to grips with.
As "Dr Phil" found out.
"Dr Phil, you say? What's your medical field?"
"What? You're a Doctor of Philosophy? Fuck off, wanker, you're not a real doctor."