The Ultimate Vampire Resource and Directory

I know people here have varying opinions on whether vampires are real or not, and I don't really want to get into that...but I pose a related question.

What is the worst example of vampire culture you have seen?

For example, I moved out very young. At 15, I was living in a different city with my best friend. He was dating a girl there who was really into the vampire culture. REALLY into it, and just being asociated with her made my life weird. There was a large group of teenagers who believed they were not only vampires, but at war.
They terrorized eachother and it often ended in serious violence.

I've known other people who were deeply into vampire culture, as I am, and were not involved in violence-so they get my worst example label.