Woolworths Returns
To quote from the Queensland Government website, regarding "Guarantees, Warranties, and Refunds".
"When you can get a refund
Refunds aren’t always an automatic right. Businesses don’t have to give you a refund if you:
- change your mind
- buy the wrong size
- buy the wrong colour.
You are always entitled to a refund, repair or replacement if a consumer guarantee is not met. The remedy you're entitled to will depend on whether the issue is major or minor."
In other words, if there is nothing wrong with the item you purchase, even if you accidentally purchase the wrong item, the store can choose to refund or replace it, but it isn't the law.
I hope that clarifies the legal situation.