Pretty rude, those whispering customers. There could be any number of reasons for a person to appear moody, even if they normally weren't. And even if they were at a cake buffet. They could be preoccupied with something important, but would still come with their significant other to the place. Their cake-loving mother could have recently died, but they are trying to get over it, yet it doesn't happen overnight. If the partner doesn't mind, why do those strangers need to mind?