I finaly caught up on the last two episodes. This isn't an awful show albiet it isn't great. Some of the shit is far fetched. I think they've setup fairly accurately how people would react in such a situation - most people panic - some have a level head. The looting is a fairly realistic expectation of what might happen. Also, the two crazy guys is a likely scenario.
I know a couple of people personally that in the right circumstances probably would easily become part of a mob mentality - don't all of us?
My only criticism of the show in terms of blending fact and fiction is I don't think the way the outside world is interacting with the dome is realistic. If a magical dome all of a sudden covered a small community in rural America - there would be a huge media frenzy around the event that I doubt even the US military could contain without shoot-to-kill instrustions on the general population. I'm having a hard time believing that such events would transpire where the people caught in the dome have virtually zero interaction with those outside of it.