Why is my profile listed in your site?

I hate being listed anywhere without my permission.
So why? I haven't registed here, I am not a scammer and... well there shouldn't be a record of me on your site.

You have no scammer tag, that is correct. Your account's steam details being shown on our site is a result of somebody looking you up on our site to check if you are a scammer. Each historical profile there is such a event in the past.
All information shown is readily available for anyone visiting your profile, we only provide some extra information, and extra links under "Quick Tools" that are relevant. We aren't providing more information then you are, but are providing links to backpack sites, TF2TP and TF2Outpost directly to your account page there (ofcourse only if you used them, if not, on Outpost you get a 404, and on TP you get "This user has never logged into TF2TP. This is a sad day.")

As such, we aren't providing information that isn't available otherwise. We just made it convenient.

I've added a "general" overview on the FAQ: http://forums.steamrep.com/threads/expanded-faq-recommended.7263/

Is there a way that I can't be listed except if I turn out to be a scammer or using the site for it's purpose?

No. We're not going to add functionality to make exceptions, especially when its policy not to make exceptions.

Others are using the site for its purpose. They checked you out. Same goes for you, you can check other accounts out when you are trading.