I agree taking it to the authorities is likely to do more harm than good. Was in my local WOW yesterday and had a casual look to see if mysteriously supply of the eftpos GCs had re-surfaced. Could see a few $50s but no $100s. I think just a matter of poorly run & supplied campaign rather than any malicious intent on WOW's part.
Makes sense given WOW's well publicized problems. Coles is running rings around them as shown by good supply availability for their Mother's Day campaign.
Just my 2 cents worth anyway.