We just returned yesterday. Monday we went to DS in the evening; Tuesday we did MK first, DHS later; Wednesday was DHS then MK; Thursday AK; and Friday Epcot.
We stayed at AKL, which was fantastic, and of course no Pop Warner groups.
At DS, we saw a pretty large group heading to dinner somewhere, but other than waiting for them to pass, it certainly did not affect us. In the parks, we saw a few groups, but nothing annoying, just one instance of some chanting as a small group walked along.
DHS did close at 6:00 on Wednesday night for their private party, but that was announced long in advance, so our touring schedule worked around it. In fact, it helped to make it a low crowd day at DHS, because people without hoppers didn't want to visit on a short day.
As for the
MVMCP, we did not go to the party, but I can't imagine that any of the groups would go to that. These trips aren't cheap for them, so paying an extra $75 or so per person for a party would be extremely unlikely.
We had a fantastic trip!