You're on the right track.
The issue isn't whether someone can use a famous person's name .com for a fan site. Generally that is protected.
However, running a fan site using a famous person's .com domain does not mean they then have a loophole to get around cyber squatting & trademark law.
Trying to sell the domain name to Ron Paul is where they went wrong. Running a fan site was fine.
Ron Paul owns his name/brand/likeness/trademark whether offline or online, however the registrant of RonPaul.com somehow believes they have some sort of ownership over RP's name.