Trolls club travellers and take their money. Microsoft clubs smaller companies and takes everyone's money. Trolls are butt-ugly, smelly, have awful teeth etc. Windows has an ugly user interface.
Trolls live under bridges.
Bill sells you the proverbial bridge every time you buy something from him. Trolls tend to have huge pot bellies. Windows is insanely bloated. Trolls jealously hoard their treasures. Windows jealously hoards system resources.