Sadly, kit manufacturers thought kits were toys (which for a very long time they were) and put in gimmicks like working doors, or rotating wheels and even sprung loaded gun barrels for tanks that would never have firing mechanisms in them, so was sort of a throwback to the Britains days.
Most, if not all modellers end up just fixing the wheels, barrels, and like you the doors in place as the mechanisms are either out of scale or just crude. I think auto modellers stick the doors etc in, fil the over scale gaps and then re-define the panel lines much like aero modellers do on airplane kits with big lines, so you have lots of scope to play with.