One problem I have with homework over any vacation is for the children who have visitation schedules that must be followed. I know too many non-custodial parents who will not help their child with homework during visits.
The second problem is extracurricular activities are scheduled during longer breaks. Band competitions, sport competitions, are a couple school related things, then the scouts schedule events, 4H, etc.
The third problem I have with it, is unless it's open ended, it's just more drudgery for the child that is advanced.