I don't see a problem with taking one or two pictures. Its an experience and a way to remember the evening. I'll take pictures at restaurants when I'm on vacation. Doesn't matter if its a chain or a 3 star Michelin restaurant - if I want to remember it, I'll take a picture. I know its intimidating to pull out a cell phone or camera at a high end place but once you convince yourself that they are just people and unless the restaurant has a policy of no pictures, everyone else can just pound sand. One picture isn't going to ruin anyone's night.