Making calls out of your primary area

[bbcoach7]

This seems to be a touchy subject, please allow for my miniscule (couldn't think of a smaller descriptive word) understanding of this topic. Why is it a no-no for one official to tweet, and make a call in another officials primary area? Is there a rule, written or unwritten? Is it because of the possible visual implication to players, coaches, & fans that one referee is compensating for the deficiency of other(s) referees? Is it simply because of egos (stay out of my pond)?

Because it doesn't seem to make much sense to me. For example (oh oh ) If durring the battle for a rebound under the basket, A-5 punches B-5 in the stomach and the official behind the end line doesn't see it, but other official does, is other official just supposed to ignore it because he doesn't want to annoy his partner?

A punch is a extreme example. I just don't understand this "turf" concept. Sure, I wouldn't stand for the opposing coach trying to coach my players, but that's way different. Officials are in charge of every inch of the court, so why not make the call if you see it?

Wouldn't surprise me if nobody wants to touch this... and that in its self is an answer

If the offensive team over loads one side of the court, or if they go "4 down" (4 players across the end line) then what? Does the other official(s) just take that possession off becasue there's nobody in his area?

Is an official really expected to just ignore a clear foul that he saw just because it's not in his primary area? (please excuse my incorrect language & don't get caught up in it, you know what I'm trying to ask).

I realize that this way of doing business has been around way longer than me and my lack of understanding it. I want to understand.