Batman vs Superman
Scene:Metropolis Rooftops night
Batman:I'm Batman and I'm here to take you down cause you destroyed this city trying to save it from Zod and his horde who would have killed us all if ...you ...didn't ...stop ...them!?!
Superman:I'm Superman and I don't like how you fight injustice using fear tactics...because...you..lack..super ...powers!?!
Both:You know what this doesn't make any sense.
Superman:We both fight injustice, why are we fighting again?
Both shrug their shoulders and walk away.Well Bats drives off while Supes flies away.
Superman/Batman team up
Scene Gotham docks night.
Superman:Hey Batman you want to team up?
Batman:Ummmm....No.
Superman:Why not?
Batman:Well for starters there are super powered people who would make a stronger team up partner then me.
Superman:But they don't bring the level of ummmmm ummmm ummmm?
Bruce you have your uses.
Batman:I never said I was useless I just said there more compatible partners for you.You and me teaming doesn't make sense I uses stealth maneuvers and specialized tools while you use super speed,heat vision and various other powers which is as subtle as an atom bomb.We would just get in each other way plus I would only slow you down .You would be to worried about me getting hurt to fight at your full potential.
Superman:Okay fine.
Justice League
Superman:Hey Bruce we're putting a team to gather want to join?
Batman:Two question,one is it station in Gotham and is it a secret?
Superman Umm no and define what you mean by secret?
Batman:I mean will people know we exist?
Superman:Yes ,is that going to be a problem?
Batman Yeah kind of ,you see I'm kind of an urban legend around these parts.Being publicly known would kind of ruin my mystique.
Superman:Gordon knows you exist your villains know you exist how are you an urban legends?
Batman:They know but the common street thugs don't.Due to the various equipment and tactics they have conflicting reports about me and GCPD tends to pretend I'm just a myth around them to spoke them even more.Beside what do you need me for the other fill up the ranks rather nicely.
Superman:Well we could use a space station.
Batman:And You and Green Lantern can't hollow out a part of the moon and/or a random asteroid for a base why!?!
Superman:Oh yeah.Sorry to bother you bye.