It shouldnt be up to company policy, it should be up to what your award specifies.
And I really doubt according to your award they can just make you do one week worth of training without pay...
But of course, they probably can if they are using the system to their advantage, which they probably are.
I'm suspecting that your hired on a casual basis. Did you sign any documentation indicating that you were going to start working on the date you started training? If you didnt, they've got you there and theres nothing you can do about it. So technically if you didnt sign anything, your not starting work, which means your award doesnt apply, meaning they dont have to pay you anything yet.
And even if you said "since your not paying me for training, im not going to come, ill just start work when i have to" Theyre just going to fire you. Well they cant fire you, but since your a casual worker they can stop putting you on the roster, which is essnetially the same thing as firing you, although a lot more funny in hindsight.