You sound so certain. They found some skeletons and made the claim that the Egyptians would not bury the slaves in the fashion that these skeletons were buried. Because of the proximity to the pyramids and the toil these skeletons show, these "workers" must have been the ones to build the pyramids. Therefore slaves didn't build the pyramids. Its a spurious arguement. It doesn't account for the possibility of some workers and some slaves, or whether some slaves were treated better than others, or whether these "workers" could of had labor intensive jobs that weren't the pyramids, or any number of possibilities.