I think this is very realistic - the real doomsday preppers are heads down in their bunkers, waiting out the disease, not running about in a group without real preparations, providing the entertainment for the rest of us. Real survival is probably far less daring and far more boring - reduce mobility to zero, lock the gates and doors, go above ground where zombies can't follow, and wait for rot to take its course. Zombies who have decomposed down to stumps will be far easier to deal with. This show is about what's left, people mostly unprepared but living on the margin of survival - guns and guts, but often not enough tactics and strategy.

Folks who have the wherewithal to have all the preps will suffer a high casualty rate in a scenario such as this - I bet at least 50% won't make it to their vehicle, another 25% will drop during attacks, and the rest who aren't allied with enough force to resist zombie waves or get to effective shelter will fall, until there really aren't too many people with the forethought to put comms in their vehicles. Comms with rechargeable batteries. I seem to recall that the deputy (Carl?) started with a couple HTs taken from the sheriff's office but without spare batteries or the means to recharge. And those fell off the story line, left behind or left without a charge, or simply left off because no one was within range to answer. Not having rechargeable comms seems criminal if you're of a preparedness mindset, but probably all too common in a Georgia rural county that hasn't funded their Sherriff's office (with DHS funds) to ensure recharging during disasters. Disaster response plans almost always are predicated on the cavalry coming from a higher level of government or national organization: most response plans progress from local, regional, state, federal - here there are only rapidly overwhelmed local, state and federal assets - DHS, FEMA, DoD, etc. The cavalry with reliable comms never arrives.

Stupidity and mistakes are common during everyday disasters. In this scenario there is no authority to prop up supply lines, ensure water, provide some form of communications, safe shelter. They are on their own, and mistakes will be made. I suppose in a zombie scenario stupidity and mistakes costs lives, whittles down the group, exposes more danger. Until an infusion of assistance - like the huge looming prison beyond the trees, why wasn't at least the deputy acquainted at least with the location of local lockups (excellent zombie-resistant shelters) so large? He might have been, but he obviously wasn't thinking enough about the real crying needs of his group - water, food, safe shelter. Given the first two, any jail makes a pretty darn good shelter. Also I am a little surprised that in a nation with over 400 million guns, they aren't finding them littering the streets. Besides ammo, keeping weapons clean and operational would be another issue, but that probably falls below the line of TV entertainment.

Although there is someone pretty prepared in this, whoever is hovering around in the civilian helicopter. I haven't followed the series religiously or read the comic book version of Walking Dead, but eventually I know they'll encounter helicopter person.