From an ethical perspective, the fact that all Arby's locations pay the same doesn't sound that outrageous, but I don't work in fast food so maybe it's really a tragedy.
The whole point is that they don't; that workers have been barred from seeking jobs that would pay better at another franchise.
Unfortunately every company operates that way; once you accept a lowball offer (which you usually don't even know is low due to salary secrecy) you can never get out of the hole except by quitting.
... or getting a competing offer.
What if one is closer to your residence? What if it is closer to your kid's school? What if you have an abusive or terrible boss at one?