It's a disguised ad - this event is free, yes, but its not purely philanthropic or a casual gathering of like minded souls via roadfood.com- it's meant to showcase a particular person and their venue as well as some other businesses, with a view to encouraging people to buy further. Which is admirable in itself, but still an ad.
there's no such thing as a free lunch.
As a DC resident, and foodie, and active on roadfood, I'm glad to know about the event, and hope this thread stays right here.
I had planned to leave on vacation that afternoon, but I might stick around and leave Sat morning.