I think you're leaving out another possibility: that they actually think they're right. This obviously doesn't apply to all cases, but I do think it's more common than you would think.

There's also a (related?) strong desire for consistency, which is explored in "Influence - Science and Practice" (Cialdini), which I found sheds some new light on the material in "How to win friends and influence people".

[Also, welcome to lesswrong]