It's a loss leader temporary promotion. If they can manage to not leave their customers feeling screwed by disabling purchased gift certs or mypoints accounts, they will have generated a definate opportunity for continued business. If they start invalidating paid for gift certificates, then Tupperware is the one committing fraud.

They could certainly change their programming to not allow $1 gift certificates, it certainly doesn't require any hacking or fraud to make the purchase. Mypoints could put a dollar limit or gift certificate restriction on the promotion, like is in place with other merchants. Amtrak was giving away 3x the number of points (2,450 mypoints) for ticket purchases of $1 or less ... they simply changed the rules of the promo and went on.