when I was picking vendors I went to an insane amount of them so I could compare prices and quality of service, and there were definitely a few that were very overpriced, but I think it was across the board rather than just based on where my wedding is. the ones i ended up going with did just as good (if not better) a job than the others. the only time i think it's reasonable to charge more depending on your venue is if the person has to travel a great distance - many companies will put that in their contract.
I guess I mean more like they suddenly decide you have millions to spend when a second earlier they seemed to understand your budget (a fair budget).
