The soldiers didn't kill the gangsters nor did they bother to capture them. There weren't prisons for outsiders anymore after all.
Anyway, living outside the safe bases was suffering enough.
Instead, they took all their hot weapons, retaining only the basic cold weapons for their self-defense, essentially robbing them a leg to take advantage of the weak.
Any sign of rebelliousness would be met with a strong voltage that would leave them half-dead.
It was so horrible that by the time they left, the gangsters even thanked them.
Except for Khalifa's almost rapists, of course, as they received several more shocks after that.
Even if they survived, they would be weakened. They'd be too focused on their survival to take advantage of others.
The group continued on their way for a few more hours, encountering small hordes of zombies the team dealt with using the 'confiscated' guns.