As customers are accustomed to gift cards' applying to the full cost of a purchase, this caused quite an uproar, with sales staff being abused despite no fault of their own. However, this gesture may well have been a generous one considering how liquidation works, for gift card holders are creditors to the issuing business.
Gift cards are debt
The Framework for the Preparation and Presentation of Financial Statements (AASB) concisely defines a liability as:
...a present obligation of the entity arising from past events, the settlement of which is expected to result in an outflow from the entity of resources embodying economic benefits.