I have an intense new peeve developing, oh yes I do. Once you notice it, it might be your peeve too.
The validation theory says that any manner in which, say, Adam is different from James will serve as a point of insecurity to James. This insecurity will compel James to demean the difference. So if Adam has a newer car, he's too material. If he has a pretty girlfriend, he's shallow. If he loves his career, his priorities are out of whack. If he believes in a different god, his every stumble is evidence of a spiritual failing. And on and on.
My peeve, then, is a subtle variation on this, and it can be neatly summed up in two condescending words: no wonder.
The loyal Microsoft employee, learning about any one of the million things I hate about Microsoft: "Oh, no wonder you dislike Microsoft." (It must not be that the company is unlikable.)The love interest, learning about my family: "Oh, no wonder you [insert whatever my flaw du jour is]. You're broken!" (It must not be that her expectations are unreasonable.)
The Seattle person, learning that I live in the sticks: "Oh, no wonder you don't like Seattle. You don't live there, silly!" (It must not be that Seattle actually sucks.)
Now I'm watching for it. I'll be discussing, say, the new smoking ban with a friend, and we'll be disagreeing. Now, if they weren't my friend, they'd just dismiss our difference as the result of my stupidity/bleeding heart liberality/redneck conservatism. But I'm their friend, and to diminish me is to indirectly diminish themselves. An accommodation must be reached in which a) I am still a worthy person whose friendship is an homage to themselves and b) the insecurity-exacerbating difference between us is still diminished. Hence the beauty of "no wonder." It's a surgical strike, an invalidation-seeking missile. It's the hook on which they can safely stow the invalidating difference. It's line-item validation.
Whatever your metaphor of choice, it's also pretty insulting.