Why do I have accounts that I never made?

Just a moment ago I shut down an account for a website I don't ever remember even going to in the first place, it's called Qoo10, a shopping website mostly restricted to Asia (I live in the United States.)

Another similar thing happened to me less than a month ago. I had to close an account on a shopping website called Fab, although I never recall using it before. I even had an app on my iPhone for the website, although I definitely did not download it myself.

The only reason I noticed these two websites is because they spammed my email inbox with several messages a day, which started to annoy me. Reading the fine print of the email they said if I wanted to stop the news letters then I have to go to the websites and log in. I did so with password reset services, and terminated my accounts.

My question is, how does this keep happening? It's not as if I register for websites in my sleep.

Obviously you have made them

Just like sleep-talking and sleep-walking, you may have a syndrome of sleep-signing (cheesy) lol
Well have you read any terms and conditions before you sign-up for any accounts before? There are times where you're account information can be reused by affiliates of that specific website.

If so, they're not really considered spam since you've agreed to the websites terms and conditions to reuse your info. Also if they went through your inbox smoothly and not to your spam then it's that most likely the case.