I have no idea how old she is but Circumcision is much common in the over 40 age group in Australia and sort of 50/50 in the 30-40 age group depending on the part of the country. It's only in the under 30s where circumcision is extremely unusual.
It's also possible that she's so dumb that, like many American chicks, she doesn't really know what it is and has fucked lots of uncut guys without even knowing it and is just parroting shit she's heard American bimbos say on TV or online.
BTW, for those of you non-Aussies who don't know 'bogans' are roughly the equivalent of what you call white trash in the US. The difference is white trash traditionally referred to share croppers and other rural lower class whites whereas bogans are more like trashy lower middle class suburban drewllers who shlumpr around in trackie dacs.