Sachsenahusen is well organized in terms of visitor's resources. It is an unique place in that it was converted, after WW2, into a political prison by Soviet invaders, an.d then used by the equally evil puppet DDR regime for political exploitation. This is a different fate than that of Dachau or Awschwitz.
The museum, audioguide and/or information signs cover well all the iterations of the site, giving insights on how, in some aspects, the horrors of the Holocaust were followed by the horrors of Soviet occupation and then the communist police state. The curators did a great job in contextualizing all these three periods without making cheap comparisons.
As for the comments about children being festive and goofing around parking lots, I think it has in part to do with the fact that, as with any great tragedy, natural or man-made, the emotional impacts of events progress from 'something that affected me or my parents' to 'something that is historical'. Most Americans, today, won't feel much grief for the mass causalities of the Revolutionary War, as more than 10 generations passed ever since. Kids being born today will not have the same emotional relationship and involvement with 9/11 as people who witnessed the event as adults. I don't think these kids are disrespectful on purpose, just that they are not emotionally connected to events that happened 60 years before they were born.