I think sometimes we overlook the obvious, Callum is arrogant, no denying it but he wasn't always and now he's a cat1 referee, maybe it's the system and not the person that needs to change.
On the point of refereeing being a hobby, look at what the refs do as a 9-5 , to use Callum as an example he protects children from the dregs if society so maybe that plays a part in his demeanor.
I'm not being on anyone's side but there's always a bigger picture, it's easier to see if you don't have an alliance to any club in particular...