Thanks for the vote of confidence, Paul...but this circus needs a Navigator and Wagon Master like Ward Bond, not a Mayor!!
Since the theme of the whole project is ROAD FOOD, I suggest a Road Trip, rather than a convention in one location. Pick a starting and ending point and a series of stops within reasonable driving distance, taking Roadfood Pot luck at the stops in-between. The usual convention is a 3 or 4 day gathering of whomever is involved, so make it a 4 day Road Excursion.
With those parameter's The possibilities have real potential... My first suggestion would be a St. Louis to New Orleans Trip, following the "Blues Highway" U S 61. with one stop being Memphis for sure. Others could be Chicago-Omaha, Memphis-Houston,Portland OR to LA, and of course Portland ME-Philadelphia.
Shorter distances are also a possibility Like St Louis-Kansas City or the Gulf Shore of LA-MS-AL-FL.
To me, for roadfood to achieve it's level of importance in the total daily schedule, travel must be involved !! I really enjoy the discussions about places with potential for dinner etc that my wife and I share while on the road....and the discussions become MORE important as the mileage increases and the hunger level grows !