I don't think anyone has specified that ANG couldn't be a highly public place - but really an obscure location is probably better, because not everything that hangs out there is human, and if they're going to meet there it might be best if they didn't have to veil themselves to do so.
What about a local hobby/gaming shop? Sorta a different take on the book store tho.
An old style theater could work, or perhaps a person's house/mansion?
I think it also depends on what you want out of your ANG. If you want a "local hang out for the supernatural" then you're really pidgin-holing yourself into a place people can get food/drink.
If you just want a place to meet for formal meetings and Accord neutral business, any place could work really - a rental hall, all the rooms in a hotel on the 13th floor, or even an upscale, members only roller/ice skating rink.
Personally, I think I like the idea of a Jamba Juice that is ANG.