Looks like a refugee camp gone bad. Maybe the walkers with the tied hands were people detained?

 

Yeah, it seemed to me that the military was in the process of trying to turn the carnival into a survivor camp [although they don't seem to have finished the process], and perhaps some of the civilians were not cooperating for various reasons, and they tied a few of them up. Although tying someones hands with bulky rope, and positioning the hands in FRONT of the prisoner isn't how trained military would probably go about it. But I still think that's probably what they meant to be the backstory.

 

Many of the army guys still have their rifles on their back. Any good explanation? If the camp was in chaos in the last moment just before total collapse, most (if not all) soldiers should have their weapons drawn out. I wonder how the soldiers were killed. They could not have been killed by chaotic friendly fires as they still have weapons on their back.

And it does not look like they were ambushed too because if so, their guns would be collected away. Not to mention that there are tons of ready-to-eat food around which means the collapse of the camp was an internal one rather than caused by an external one.

 

Yeah that didn't make a lot of sense. Maybe a bad batch of mac & cheese?

 

It was the Chili

 

Probably a similar situation to Fear in season 1 where the military came in and the situation quickly deteriorated.