I saw one analysis that I thought was spot on: Emotionally, when prices go up, you process that directly, but when you get a raise, you don't see it as because wages and prices generally go up together as part of the same macro economic effect, it's because YOU, as an individual, earned IT. So even though you are keeping up, you don't process your wage increases as inflation cancellation the way an economist would tell you they really are.
I think there a kernel of truth there.