I feel it does become confusing if those whose names appear on local memorials are not or were not actually born or lived in that area, And also it seems that the names are placed there by family members who perhaps lived in the area to honor their family members who served etc.
I would think it depends on the type of memorial, as to my understanding, the Honor Roll is for all fallen servicemen and women, but I am possibly wrong about this.
Have you contacted the Australian War Memorial in Canberra?
Good luck Toni Grahame
Feel free to share your research on the Discovering Anzacs website - http://discoveringanzacs.naa.gov.au/ .
Once you register, you can add locations of memorial against the life events map and list for a person.
It may assist your research, to take a look at Advanced search and type, Cranbourne as place of birth or place of enlistment.