Okay, what happened to me is that I entered bazaar.tf to check on my offers when I noticed that a person called "Slapstick Salami" referred me and that I earned credit for that, though the user isn't friended with me. I asked him in Steam (on his profile) if he did that intentionally and he said that he has no idea how that happened. I asked him then if I should report it, he said that I can, so here we are!
Proof of him referring me (while this thread was being made :D)
Proof of him saying he never did the refer (Steam)
- Dammit, Hoji, no bad jokes!