It would be hard to put a continuous wall around. I think the mall park is like 300 acres. So they'd be safe inside the buildings but not outside. Plus its risky making such a famous place your home, because other groups out there might also head to D.C. and you can end up with unwanted visitors. Obscure, hidden places like Hilltop are more secure. And there are advantages to keeping the communities separate. This compartmentalizes things, and if one place falls or gets overrun, the others remain intact.

 

Given the problems of the sanctuary, why wouldn't they find a better location closer to the other camps. Including with better farming land. There is no reason to stay in the factory. But its a plot point.

 

They've had 18 months, certainly - we might expect them to have predicted the failure of the first crop and moved immediately, to any one of the locations that could support all the workers and the work they do, after resources had been expended uprooting and moving that population safely and swiftly with everything they'd need once they got there. There's not a single reason to stay, after all, apart from all the compelling ones.

 

As much as I like the show, they do do some stupid things.
like going to DC to find a plow, a dug out canoe and a covered wagon.
1:They probably passed 20 farms in the past two years that had newer plows that could be converted to be pulled behind a team of horses.
2: You need a model of a dug out canoe to make one? Really? We learned this technique in grade school. You build a fire on top let it burn into the log then dig out the charred wood. Not rocket science people!
3: A covered wagon? Really? What they need are flat freight wagons sometimes called drays. They are better to haul things, the covered wagon was meant to live in while you traveled across the country. Whats wrong with the wagon they were using on the trip to DC. It's got modern tires (no shortage of cars to get replacements from) as opposed to wooden wheels with wooden spokes that are way weaker and a pain to make. Any farm around the area will have a hay wagon or trailer that could be converted by adding a yoke and harnesses.

I can understand grabbing the heirloom seed stash, that was the only thing that made some sense, though again, they probably passed a few grain elevator/seed outlets on the way to DC.

 

Technically you are right, but as one of the producers, can't remember his name, said on TTD, they wanted to give the show a "western" feel, and this wagon fits exactly into this theme. Just like hanging Gregory from a gallows.