This discussion may contain spoilers!
Maybe there are in fact, two communities. You have the manipulative Carver-community, which is why Bonnie went there since she was a junkie and is easy to manipulate.
And maybe on the other side there was Tavia's community? Perhaps somewhere down the line the two communities (for example, Luke finds the other community, joins up with Russell, Wyatt, Vince, Eddie, Shel/Becca) will fight and somewhere near episode 4 the final -endgame- group will shape up depending on the choices?
Perhaps Christa found the other community. And Roman & guys got killed by Carver's group.