Are special degrees just an advertisement?
I will answer this part of the question:  "when you apply for PhD in USA?"

Faculty in the USA know very little about Australian degrees and Australian universities.  They will only appreciate the difference between degrees if you explain it to them in your application.  

To be eligible for an American PhD program, someone with an Australian Bachelors will need an honours or a masters, because three year degrees are not sufficient.  Expect to need to explain what an honours is, and that it is not like a UK honours.