Don't want to sound sanctimonious but what is so wrong with Qantas doing this, as claimed? You can be sure that many other employers have all kinds of limits on Internet use.
Having been a manager and supervisor, and employer, I can say from experience that Internet access is a great time waster. Most employees do not require Internet access to do their jobs and the tools are readily available for any employer to limit Internet access not only to those who genuinely need it but also to restrict access to sites that are required for an employee to do his or her job.