I know exactly what you mean. When I remodeled my kitchen a couple of years ago, I found that the walls were way out of plumb. I hadn't intended to tear out all of the sheetrock, but the out-of-plumb condition sealed the deal. When I put up new rock, I used drywall shims and had to cut a kerf and sister on a couple of the 2 x 4s to get the wall where they should be. Some of it has to do with the relatively poor framing materials used in the last several years, but when I checked form plumb from plate to plate, it was clear that the walls weren't framed plumb. Anyway, it was worth the effort. The new wall cabinets went up like a dream, without any additional shimming. Also, my glass subway tile backsplash went on without even a hint of lipping. Did I mention that I HATE everything about drywall????
I guess I shouldn't have been surprised, but I was. My house was built as a full custom job and way overbuilt throughout. I expected better.
Gary