I agree with Thor's comments. You need to be in the right place for a shop like that to work. Preferably a very large metro area that combines a heavy urban core and a good amount of pootling land nearby. This would be so that you would have folks that might be interested in all your offerings (from commuting to touring).
I don't know which places in Oz would work for that, but in the US I would guess at major cities in the Northeast, Chicago, and perhaps some second tier cities like Portland that happen to have a large bike culture already in place. There are no cities in the southern half of the US where such a store would work to my knowledge unless it relied heavily on internet sales.
I've lived in Florida for most of my life and a store like that would die within a year. Just not enough people looking to buy folders as there really aren't any dense urban cores despite having multiple cities with 1 million plus people. Also... until recently land was cheap so most apartments and homes are on the large side so no need to fold unless you're traveling.
--sam