I wouldn't be too hostile to us Baltimore folk.
I've only ever had a person ask me what was going on once in...2001. Most of the people I talk too around the city (before or after Otakon) know what it is. I mean, just mentioning "People in costume" will make them go "OOooooohh that thing!" They've been in Baltimore on and off for at leasta decade, so hopefully most people would be used to it by now.