The flight from La Guardia to Halifax is a cinch: A small plane operated by Chautauqua Airlines for Delta gets you there in less than an hour and a half, and makes it hard to believe you are traveling to another country and have to bring along your passport. So it was with what you might call careless abandon that, in the air headed to Nova Scotia, I filled out a Canadian customs declaration. Too much abandon, as it turned out. Just exactly why I answered in the negative when ticking off the query that asks if you are bringing in food remains unclear even to me.