I agree that $500 doesn't net you much profit, but I do not think that $500 is unreasonable. Considering
availability and target market. If it's only available at Disney Land/World, or a Lego store, but advertised well so that people know it exists, then there will be a great demand. The CMF line is proof of demand, I believe.
But not everyone has access to those outlets. I live in Florida, and the closest Lego Store is in Orlando in Disney Springs (VIP points, freebie and 10% Season Card holder discount would whittle down that $350 price tag some), 2 1/2 hours away. Imagine a scenario where Christmas comes and LEGO Shop at Home is sold out. Not hard to imagine. You can only get one in a Lego Store or at a Park. $500 piece a cake. Why? Target market. People who can pay $350 for a Lego set, can pay $500. A park ticket for one plus the set would easily hit $500. If you don't already have plans to go to the Park to get one of these, $500 is a deal.