I would only ever run an "All-Evil Campaign" if all your players are very good and you trust them and/or you have some rules and guidelines to keep them focused. There is an excellent 3rd party Pathfinder adventure path called Way of the Wicked that pulls off the "All-Evil Campaign" really well. The party must be Lawful Evil, right from the get go the plot establishes a great reason why the party should be working together, and a diabolic contract makes sure they wont try any funny business with their boss.
Even though you're not the DM, it still doesnt mean you cant talk to other players one-on-one and discuss their actions with them. They're your friend (hopefully) so just bring up what problems you have and try to sort it out