As has been already written - the +8 for Ranged Combat was put in place for balance reasons. They arrived at +8 solely because +5 was not deemed enough, and +10 was too much. Really, that’s pretty much it. The combat system is not real life, so stop trying to wrap real life examples around it. There are certainly points at which the combat system breaks down. For instance, the +8 modifier does not take into account shorter than optimal range to target—this includes Point Blank range. By the rules as written, you are using a firearm, and if the projectile travels more than an inch from the end of the barrel, you have to apply the +8 modifier. Does it make sense??? If you hold a pistol to someone’s head, should you apply the +8 modifier?? The GM is fully free to adjust the rules to their own purpose - AO is no different from any other RPG in this respect - really! it’s right in the book! GMs can change whatever rule they want for their home campaign. I myself do not use the +8 modifier within a certain range, but rather reduce it appropriately, and at point blank, have no modifier. And within one or two gaming sessions, you can sink enough points into your Ranged Combat skills to negate the +8 for your favorite firearm if you’re really serious about it.
As for ranged vs melee combat, I’m here to tell you that the rules system favors melee combat. Believe me, I see it abused every home game session. Only wielding is more powerful.