LiquorLand Australia

On the evening of Saturday 2nd January, my family was attending a social gathering and I chose to stop and purchase alcohol and cigarettes' at a LiquorLand at Victoria Park, Perth.
Two adult females (30-40yrs) (relatives) and my daughter (11yrs) entered the store and preceded to choose a product (beer) to purchase, they approached the counter and a female staff member refused to serve them stating they were in company of a minor.
Following a short conversation they left the store and returned to my vehicle, and suggested we had to go elsewhere.
I then entered the store and attempted to purchase the same product. I was told I couldn't be served as I was in the same group. When I questioned the reasoning I was advised that my daughter had entered the store and was under age. Also she had no ID. I might point out that the only ID available to an 11yr old is a Primary School Library Card, which is not a legal document, and I do not suggest my daughter carry her passport to a social function. At no point was there any indication that my daughter would consume alcohol or that the purchase was intended for her.
My daughter regularly accompanies either myself or my wife when shopping and these shopping trips often include the purchase of alcohol.
I have never been refused service due to her being in my company.
However I will now avoid Liquorland and advise all my contacts to do the same. Until staff have been trained in the correct interpretation of the applicable WA Legislation.