Holy cow!  According to this article by the Australian Herald Sun 30% of the $1.2 billion Australians spend on gift cards this year will go unspent.

The main reason seems to be that Australian law doesn’t restrict expiration at all and my gift cards expire after only 12 months.  Another difference between Australia and the US is that the government allows retailers to keep all the breakage as profits rather than turning them over to the state as unclaimed property.