I was basically kidding you :-)
(although a bought account seemed like a remote possibility, too)

The info posted by Muhammed Zakir is pretty extensive and should answer all the concerns around "possibilities".
One thing that must be understood about low probabilities is that astronomically low probabilities (for example, for private key collisions) are for all practical purposes equal to "can't happen", but mathematically they are still not zero. This often confuses people who never deal with really large numbers.

Onkel Paul