Its tough to mention sit-ins, because there’s no choice involved. You either go to the house (nice or dumpy) or you don’t. Or you go to an “off site” house, where the little brothers / sisters / neighbors are not around to offer their input.
I respect your choice to have your kids sit in, but IMHO if you’re old enought to get married, you’re old enough to go out by yourself. But then again, I have friends who’s mother-in-law and kallah set up the chosson’s dresser drawers the week before the wedding, so maybe they really can’t be trusted to take a train on their own. (forget driving, that’s a given to be a no-no)