NSNF Protocol

Last night I went out to dinner with my partner and we went to a Sushi/Oriental place of his choosing. I ate a cup of lettuce with just about 1 T. of toasted sesame dressing. (I dipped lettuce in dressing on the side.) For my entree, I had broccoli beef. No rice. I know there was some sugar in the brown sauce that was mixed in with the entree. Is this a broken protocol if I am eating NSNF? This was the best choice on the menu. What do you recommend for the next time–when discovering menu is not ideal, ask to go to another restaurant? The waiter did confirm there were small amounts of sugar in all their sauces (I asked). Is this a minor amount that once in awhile is okay, or should I also eliminate this restaurant from some place I go?