I think the thing that scares people is the idea of lack of control over what happens. A crime that seems more random, more unpredictable, more just a sudden impulse of some disordered person, is more feared, especially if it happens in their home, which is supposed to be their castle. They're safe there, nothing should go wrong there.
If a person is outside their home, then people can kind of say, 'oh, well, they shouldn't have gone to that place'.
The thing people fear the most is the randomness of events - the 'non-deservedness' of events.
We have long experience with religions and cultures in which the victim is blamed for whatever befalls them. They have sinned previously - in this or another life, and this is punishment. Or they were ignorant, or didn't respect their elder's warnings. So they are harmed because of some action of their own.
In the same way, people react to news of a disability or disease as if they had some control over it happening - they will blame it on some event that clearly can't have anything to do with it.
WHY? Because people love having the illusion of control - that comfortable idea that if you do A, B happens.
The trouble with these strong emotional reactions, is that generally, people are actually far more likely to be a victim of a crime close to home - at the hands of someone they know rather well. This is true of crimes against children as well. They are usually committed by relatives, friends and spouses.
What happens is, people actually guard against the types of crimes they are MOST UNLIKELY to become victims of. It's ironic, but sad. People actually leave themselves open to much more likely crimes, by guarding against things that are exceedingly unlikely.
People should have bars or security screens on any windows that are easily accessed from the ground level, in any area - rural or city.
In a number of cases, residents in the house have turned out to be responsible for crimes against children. The area is often staged to make it appear that a breakin occured.
So without having read the Australian case, I still can say that whatever did happen there, we're wise to take steps against the crimes most likely to affect us, not the least likely. Of course families who have experienced acrimonious divorces or have spouses or other relatives who feel they were wronged at the parent's hand, need to be extra careful.