Cthulhu Live (long?)
I don't believe certain types of LARPs are freaky at all. In fact, the LARP I enjoy most hasn't even been mentioned:
Cthulhu Live.
The only other LARP I have participated in was one of those IFGS variants, which I didn't really enjoy. The plot was fairly limited... The players were just a band of people hanging out in a shack and waiting for "elementals" to show up and direct the plot. I'm pretty clumsy, so things got real ugly real fast. The group was more into "hack n' slash."
I have only observed WoD games, but I believe, as another poster stated earlier, that Vampire players prefer to be super human and possess an advantage over mere mortals, as well as other players. This may be an askew view, but it is one supported by other accounts. Its just not my cup of tea.
Cthulhu, however, is dark and gritty and the odds of survival are infinitesimal for the good guys. Heavy role play is abundant in most scenarios, but combat based ones are also possible. No rock-paper-scissors here, instead, players are supplied with a wound card listing what every bullet will do them; whether the next bullet will be a hit or a miss. The sounding of a cap gun brings fear into every character's heart.
So Cthulhu Live LARPers tend to be less into incessant theatrics or mindless combat. They want a balance in a darker setting. That's my experience with LARPs.
(Unless you count that time I led an attack on a Vampire LARP to deprogram our group's DM... Nine Inch Nails drove them vamps outside good. What a sight it was, a half-dozen gamers, hopped up on Mountain Dew [or the Faygo equivalent], armed to the teeth with foam stakes, yelling out "Hoody Hoo!" at the top of our lungs whalst we ran into the heart of the enemy. We had been deprived of DnD... We were unstoppable.)
-Apologies to Knights of the Dinner Table