Don't confuse this with 'pilot choice' to not want to hand fly to the published minima. Someone in the Aviation Authorities has made these regulations up, why... who the hell would know. Here is the cut and paste from the Australian AIP.
a. minimum visibility 1.5KM is required when precision approachCAT I lighting system(alsoknownasHIAL) is not available;and
b. minimum visibility 1.2KM is required unless:
(1) the aircraft is manually flown at least to the CAT
I DA using a flight direct or approved HUDLS;
or the aircraft is flown to the CAT
I DA with an auto pilot coupled (LOCandGP);and
(2) the aircraft is equipped with a serviceable failure warning
system for the primary attitude and heading reference
systems; and
(3) high intensity runway edge lighting is available
So basically you can't go below 1.2km without high intensity lighting, and flying an autocoupled approach with flight directors and a warning system.