Is anybody stealing my passwords?

Sometimes I accidentally sign in somewhere with the wrong password. It's especially common since I have whoeverthefuckiam for my user name more often that not, so I'm used to typing it then one of several passwords. I wonder, when I enter a password that's wrong not from a typo, but completely a different word/number combo, I wonder if, say, some evil technician at google, for instance, tries to use that password with whoeverthefuckiam@something.else, or whoeverthefuckiam on amazon or ebay. That seems like a good idea for identity theft.