I have a colleague who would regularly fill an entire carry on rolling suitcase with wine when coming back from Europe. (Probably like, 6-12 bottles)

He would declare it, and every time CBP felt the time involved in calculating duty and arranging payment would cost more (in terms of personnel costs) than the duty and waved him though.

Similarly, driving into Canada I declared I had a handle of whiskey. After a little back and forth on the unit conversions, we were told duty free limit was 40oz for spirits, I had a 64oz bottle of Kentucky Bourbon, and not to worry about it since I was honest and declared it.