Sellers should always make sure there will be a responsible adult around to care for the animal. Pets are a HUGE responsibility, they are living creatures! Such a seller probably wouldn't be tempted into fraud if s/he knew there would be a knowledgable adult recieveing the animal.
A minor in this situation should have informed the household of their impending arrival, and, should the animal be 'defective' (dead, unhealthy, etc.) they should most definately recieve the money back or a replacement. Any reputable 'dealer' will offer certain warrenties and put them into writing before a sell is even finalized.
Just a question, what made you think of this topic?