Since I cross the border using a RABC permit, the only person asking us how much liquor we have is the ranger, whose interest - it seems - is more sociological than bureaucratic.  Last trip with a crew of four we took along 7 liters.  The ranger was amused by that number.

Back when there were manned customs stations "near" the ranger stations, the PP customs officer said next trip we could leave beer off with him and he'd keep it chilled for us to swill on the way out, just make sure there was some "excess" he could "confiscate".  Never got to test him out since the next year they closed the customs stations down.