My employer (more specifically: HR) keeps opening website accounts on my behalf (using my name, work email and DOB) on websites. Some are work-related, some are not, but in no case are relevant to the job that I'm doing.

How can I let HR know that I don't want this (I'm happy to forfeit the benefits of these website, as they don't apply to me/I won't use them at all). Should I argue with privacy, which I'm concerned about (running the risk of bewildering them as most people don't even have an idea of what privacy is), or should I simply state that I don't wish to have these accounts because I don't need them? 

If I knew it were illegal, I'd argue with the illegality, but I have not been able to determine whether this is legal or not (in Australia). I've found no answer to this question on the net, not even FairWorks or HumanRights have an answer. I could ask a solicitor/lawyer, but there must be an answer to this out there without spending 100 bucks in consultation fee...