That surcharge is ridiculous. If that crawled its way into my bill, I wouldn't tip at all. And no, you don't get tipped for just doing your job. I normally start around the 10-15% mark depending on the price range of the place (more at higher end places) and go up or down from there. I expect you to be knowledgeable about the menu, my order placed properly, my food delivered hot, my water glass topped up without my asking, and prompt service when I ask for it. It's not too much to ask.