No-hug zone

What does it mean that neither of my children can bear to see my husband and I expressing affection for one another? Is it normal child squeamishness, jealousy, signs of insecure attachment, garden-variety annoying behavior? If my husband and I hug in front of our daughter, she makes disgusted noises and whines, "Can you please do that somewhere else?" My son, on the other hand, reacts by demanding to be part of the action: "I want a hug too! I want a hug too!" he cries as he wedges himself in between us. We have more group hugs than a bad sit-com. Aren't kids supposed to be happy that their parents love each other? Or is that, like, just too embarrassing for words?