Fall, the new social season

When, magically, the happy day arrives in which I made In Charge Of The World, my first act will be to ban all petting zoos, and THEN I will move onto the tough stuff: redistribution of not wealth (I'll leave that to Obama) but something equally (more?) important: the redistribution of my calendar. Or, should I say, our calendar, since Flipper's social life is remarkable humming with activity for a 5 year old. What kills me is this: we go weeks-nay, MONTHS with nothing to do, empty spaces on week-ends to fill, no volunteer responsibilities gobbling up my spare time like a fois gras goose, and then we are swamped. Drowning. Racing frantically from sun-up 'til sundown with nary a moment to think, let alone breathe, or feel "balanced," a term that, when applied to the circus juggling act that is parenting, creates much rage in me. Much like "sleep when the baby sleeps."
So I want to create some sort of system whereby all of our engagements, trips, playdates, birthday parties...ALL of these fun and time-eating events are spread judiciously throughout the entire year, thereby creating ONE fun event every week-end, as opposed to four on one day, then nothing for weeks on end.
What makes fall so busy? Why is this season of beginning hibernation one of serious social engagement? I can;t figure it out. And, while pondering that incredibly important question, answer me this: when did Halloween become such a real holiday, one that involves yard decorations, Christmas tree lights that are not, in fact, for trees at all, but for fall porches. When did this happen? And can I make it go back to the Halloween of my youth, where we made some sort of costume out of whatever was on hand and traipsed through the neighborhood (your own, not someone else's) and that was it? But a really GOOD it.