For the OW bonus 7 years ago, I flew CX 888 YVR-HKG in Y on x'mas day. Nothing. Might have been a turkey dinner but I don't recall. Haven't seen anything special on PA (in the old days) on NYE (or going into NYD en route) either. I did fly NW U.S.-NRT crossing the IDL twice. On one flight, the FA asked if anyone wanted a celebration crossing the IDL but everyone (12 pax in the 742 WBC upper deck) elected to sleep.