AMC isn't looking at it like that, what they're trying to do is the tv version of the marvel cinematic universe. (the dc comics, arrowvese might be a better comparision).

Fear was meant to be an alternative look at the zombie apocalypse with very different people, in a very different part of the country facing different challenges and having different experiences.

If the show had gone well they would likely have added more walking dead spin offs set in other locations.

And that could have been great, like imagine following a group as they develop over the course of a couple of seasons and they start to have encounters with another group in what becomes a disputed territory.

This new group they've encountered does something bad to group 1 and they are on the verge of war.

meanwhile in another show we've been following another group, they start off in one part of the country but slowly move to a different area. We've been getting to know them pretty well and we like them. They encounter another group and it scares the shit out of this group so they decide their only option is to do something really bad in the hopes it scares them off.

It eventually gets revealed that we've been following two different groups on two different shows and the story is about the war from each sides point of view.

I mean thats one (poorly written idea) but the concept of a cinematic/crossover universe is super exciting and I till want it to happen.

The problem is they did a bad job of it.