Maybe he was just having a low-blood sugar moment? Witnesses say that a grumpy Jerry Seinfeld was waiting for a table outside LT Burger in Sag Harbor the other day, when “three cute little girls approached.” One of the girls asked the TV giant if she could snap a picture of him posing with her sisters. “At first he pretended not to hear her,” said a spy. “When [the girl] asked again, he said, ‘No,’ and turned away.” Apparently the girls then walked away, dejected. “Jerry is fine taking pictures, except when he’s with his kids,” said a Seinfeld rep.