I don't see how evolution has anything to do with your theory. Furthermore I doubt that the motivation behind arguing about 'pointless' topics is to sway the p

I don't see how evolution has anything to do with your theory. Furthermore I doubt that the motivation behind arguing about 'pointless' topics is to sway the population to your side so that you can benefit. Unfortunately, however, I do not have an explanation as to why people may argue over such topics though I suspect that it may be related/due to cognitive dissonance. There is a conflict between what they have concluded and what someone else has concluded. This could be for many different reasons such as different needs, different preferences, or different skills, but on the surface someone else has made a different choice for what seems like a similar task.