I was passing through SFO for the labor day weekend and tried both restaurants. As noted, it's $28 at each restaurant, not including tax and tip. In both cases, I had to scan my card in a handheld device. At the Giants Clubhouse, the bartender had me go back to the host stand and get the card scanned first. At Yankee Pier, I scanned after the meal. I wasn't that hungry at the Giants Clubhouse after Yankee Pier, so I just ordered dessert. I also ordered some cookies to go.

In both cases, I tipped as I would had I paid the full bill. Neither restaurant asked to see a boarding pass, so you could probably use this benefit on arrival.