I wish I could answer this one. I don't know anyone who is a vampire. I have had a feeling a few times that I was with one. But I could not be sure.
It was kind of tense though. I don't know why but the other person was very quiet and almost mean when I spoke with him. On the inside of his arm I later noticed a tattoo of a "Vampire Ankh". So I just assumed he might be one. Or a role player. Also, the energy in the room was intense. I felt as though he didn't care for me but I can't really be sure.
That is my only experience.

I'm sure there is some prejudice out there. I have often come across posts on other sites where people are putting each other down because of the different types of feeding. The Sang's put down the Psi's and the other way around.
I personally think we are all equal. No matter how we feed, it's that need for energy that should keep our bond with each other close. We should help each other instead of being prejudice toward one another.

I'm not sure if it's "prejudice" per say. I do think that most of the problem lies with the fact that it's a very personal and subjective subject.

There is no set right way or list of things that make you or don't make you a vampire. there are guidelines, and certain symptoms, that seem to correlate, but I have not seen anything that would constitute as prejudice.

Unless you are referring to the habit some Houses and Covens have of bashing nonmembers or other Houses for their beliefs or systems.I have seen that get down right aggresive sometimes.
( must have been what it was like in Antioch when they were trying to "standardize" Christianity )

People do seem to like to fit others into boxes. Often if you don't fit into one of their boxes it makes that person very uncomfortable.

There is much beauty in difference.

I've had this experience many times, though no one public really knows what I am. At least I don't think. I haven't had much experience inside the ovc besides adn and de, so no report there...