Maybe they only made a small amount of them, and it sold slowly. Add in the unique tooling, and there might not have been as much profit.
Just trying to think of a logical explanation for this answer. I mean, it sold out.
Here's an idea: put it in the middle of the year, instead of in December when people don't have a lot of money to throw around. Then maybe it will sell faster.
Mattel can save their Granymyr, I don't want it and won't buy it. I'll take a Battle Ram or Roton, or even one of the more crappy vehicles, before I'd spend twice the amount on some fat dragon.