I'm getting annoyed about this too, and it isn't being treated with the urgency it deserves. I declined the 6 months free subscription and yet Parallels Access was still installed on my machine. Installing unauthorised software is a serious matter, and this one has the potential to compromise system security. It also acts as an unwanted advert, prompting for a sign-up each time the system is restarted.
Yet
http://kb.parallels.com/117142 hasn't been updated, even just to say it is incorrect. The release notes for build 9.0.23062 say that "You can now choose whether to download and install the Parallels Access agent" but actually it does nothing for people who have installed earlier builds. People who declined the subscription haven't been contacted to warn them, and they should be.
@ParallelsCares? It doesn't look that way at the moment. Can you raise the profile of this with your senior management?