You know what it's like. Every year we pick up Halloween treats from the grocery store, usually two or three weeks before the big night and for some reason the supply mysteriously evaporates before October 31st even arrives. This strange phenomenon is particularly puzzling when it's something you like. Boxes of Smarties, tiny Mars Bars and potato chips are highly vulnerable while raisins usually remain safely stacked in the pantry. We have to be so careful about what we dispense these days. When we were kids, the best treats were…