My guess is that this situation is the result of invoking: dpkg -X *deb / or, simply unpacking a tarball into /. But your guess is as good as mine.
The only package I installed via dpkg was youtube-dl, as I couldn't get it by invoking apt-get install (and I still can't). I downloaded it from the browser, and true, I did not verified the package (is there a common way to do that?)
Yet, there is another thing - OP claims that he didn't install anything like this. Reco
I prefer Virtualbox and QEMU over VMware, and on this machine I had no need to install virtual machine at all - yet.
However, I used pip to install virtualenv as suggested by one python package. Perhaps virtualenv uses some VM package?