You should probably add the row Diploma to the Degree row since in Australia it is very common to get a trade certification rather than attend a typical 4 year school, where most Americans would get a Bachelor's degree for something like communications Aussies will do a shorter certification. If you do that, the totals for brothel workers and private (callgirl) prostitutes are not that bad at all.

The main problem is enforcement though, the illegal brothels are the ones that cause problems. Making the industry illegal would just put more women at risk as it would remove regulation and oversight. There's not a country in the world where you can't find a prostitute, despite it being illegal in most places.