They're not carving stone when digging out the fossils. And the average fossil digger is not Michaelangelo or capable of sculpting a negative dinosaur skeleton out of solid rock. Just imagine hundreds of people on a dig trying to get the symmetry and proportions right. The answer is that the material inside the impression left by the decaying bones is softer than the rock it's encased in.

Sure, dinos for kids are big money, but there's just a massive amount of proof they existed. What proof is there for the world being created in seven days besides a single book of stories invented a couple thousand years ago?