I watched the first season, and also caught the first episode of season 2 the other night. Your right that it is a SHTF show, but it is based on a lot of questionable assumptions.
1. There are no firearms, and no discussion of them. In a real situation there would be some around and they would be game changers. Even if the group didn't have any, the mob that came to take there stuff might have had one or two.
2. The fights obviously have to be fake. They were fighting with a mob the other night using pieces of 3/4" pipe. In a real situation there would have been some dead folks with busted skulls, or at the least broken arms or legs. There is no way to do that on a reality show.
3. In each season there has been a convenient river or canal nearby as a water source that simply needed to be filtered or boiled. For about 90% of Southern CA that is not the case and a lot of people would die from lack of water very quickly.
The part of the show that is good is that it shows people who are clueless just how bad things can get and how some of the simplest things we take for granted would be very difficult when society breaks down.
Now, having said all that, I still like watching the show and I do feel like I have learned a few things from it.
FredlyFX
http://fredlyfx.com