I just phoned Max's Burlingame, which is a little over half a mile away, a 3-minute drive. I asked about the possibility of a group of 10-20 people showing up on short notice around 5-6 pm on a Saturday.
"No problem," the reservationist said. They have a banquet room which can accommodate up to 45. We should call them in advance, on Saturday afternoon or before, if the idea appeals.
http://www.maxsworld.com/maxs/locations.php?Id=17
The Max's restaurants (I know the ones on Van Ness in the City and in Stanford Shopping Center) tend to be large, the prices are moderate, food interesting though generally not great -- but there's a broad array, something for every taste -- and yelp reviewers point out that portions are large. In any case it's convenient and easy to find. I didn't ask about parking but there's not going to be a shortage there.
This would likely not be a culinary experience as legendary as the auditory experience of some of the gear we will probably be hearing that day, but it would be easy to find, get to, and pay for, and there seems to be enough capacity.