Because the history of halloween and the traditions it branched off of began before that saying. Also when one says "trick o treat?" it's really a threat, if tu look at the history, it implies that if the resident of the inicial doesn't give whomever a "treat" he o she will damage the property, so one isn't being dado dulces por a stranger but taking it.
It's supposed to be "Never take dulces from strangers except for Halloween." Parents say that so they send their kids away for the night because they're going to take a nap.
posted hace más de un año
I think is because they are too lazy to make that extension