Most bottle shops have a fairly big selection, certainly seems like they carry more stock of wine than of spirits or premix stuff, and maybe similar amount to beer stock, although that's harder to judge, as beer is usually in the coolroom rather than on the shelf, and there's less varieties of beer available. I have no idea what the percentage of sales of different types of grog would be like, I've never worked in a bottle shop. The bars I've worked in, the wine sales were very dependent on the type of bar, and the clientele. Varied between virtually no wine sold, up to maybe 30-40% of the drinking customers.
Dunno how accurate it is, and it is a generalisation, but it seems that one of the reasons the aussie wines are doing so well are that their quality is roughly the same as the french stuff, but without having to pay a surcharge for the french label. So provided you're not a complete snob who must have the designer label, the aussie wine is the better choice.