I worked on Con staff for several years, and can honestly say that LARP games draw a much larger "weirdo" faction than standard role playing. While these players tend to be in the minority (maybe 20%) they seem to dominate many of the games. The ongoing LARPs appear to be the worst at this (just my opinion - that wasn't meant as a Troll).
On the other hand, some of the best games I've ever played were LARP games.
One was called Pope Maker, and was set in 15th century Rome. All of the players were Cardinals brought together to pick the next pope. It concluded with KidCathulu being named the Pontiff. Another one was called Comrade, and was set during the Russian revolution.
And my wife and I helped run a great Star Trek themed LARP named One Big Happy Family, set right after the movie Generations. The playing characters were most of the casts of all four Trek series in the same place at the same time. It ended with PirateCat playing the 145-year-old Bones McCoy, and lecturing everyone that everything that had taken place during the past four hours "was a bunch of space hogwash!" concluding "If Jim were here you know what he'd do about all this? He'd shoot the Romulans all to hell and then run off with a green girl." It was great fun.