Good post on your NZ experience.
Here is what a great friend of mine who happens to be a Medical Director for several large departments says about spinal immobilization....it is not needed, simple.
When someone has a fractured arm, a fractured leg...what are they doing when you arrive? They are in a position of comfort and they have already self splinted. They may need support as it is tiresome keeping an arm elevated in a certain position but for all intent and purposes, they have found the best position for them and have "splinted".
When we see this, do we start manipulating it? No we do not. We ask them if it is comfortable and we help them support it in that position.
Now change the scenario to a neck injury or a spinal injury. Do you really think the patient is going to move about when they are in pain? Absolutely not! They have already found the best position for themselves prior to your arrival....or they will soon find it if they are stuck (elderly between toilet and tub) once you extricate them from that position.
They will self splint and may need a little support for transport (such as the scoop) but those are removed once the move is made.
So why is it we feel the need to start manipulating necks and spines when the patient has already self splinted, when we do not do this for any other fracture? We can tell them to stay still and not move...simple.