When I asked the concierge at the Hyatt Regency in San Antonio to point me to some "greasy spoons" or good ol' joints, she was truly horrified.  "We wouldn't send out guests to those sorts of places - they're mostly in the wrong part of town."  The Concierge never did get back to me when I asked her for recommendations away from the touristy River Walk.

Don't know if the Bun 'n Barrel is in the wrong part of town, but it truly is one of those sorts of places.  I had the two meat platter - brisket and smoked sausage with sides of beans, potato salad, pickle, onion and barbecue sauce.  Washed down by a vanilla shake and chased with an order of onion rings.