Sometimes I feel bad for having characters/couples fight. But, they're arguments I feel the characters need to have. It's not like I'm actively trying to get them angry at each other, they just get mad like people do.
Sometimes I read stories and get annoyed that the characters don't fight or have never fought. It almost seems like bad communication. It prevents them from ever talking about things that are important to them and their relationships. Or it seems like one character is supremely dominant and what they say goes which isn't all that great of a relationship.
It kind of reminds of that episode in Bones where Mr. Abernathy tells Brenan that she and Booth are about to have a fight and he can tell by their politeness to one another. If characters never fight or at least have serious discussions about their problems, then it feels like they're just being that sort of polite.