What an interesting question. Hmmm. Okay, so John and Patsy supposedly find their daughter dead on the morning of December 26th. They never return to the house once they are shooed out of it. At best, they have Pam retrieve some sentimental curios and clothes. They then spend all their time post-murder supposedly so out of their minds with emotion that they can barely eat or sleep.
So do tell, John and Patsy. How did that scarf John bought get into his hands in Georgia? Obviously he had no ability or desire to buy it after JonBenet was dead. And equally obviously there was no innocent ability or desire to ask Pam to retrieve it from the house as a sentimental curio, since it had never belonged to JonBenet while she was alive. So a reasonable circumstantial case can be made for the theory that John and/or Patsy knew the scarf was the initial ligature used in JonBenet's death, also knew it could contain trace evidence directly related to either JonBenet's bed, the basement crime scene, the ligature cord, or body fluids, and therefore one or both would have had motive to literally bury this evidence.
I join the call. This scarf (which is conveniently also not identified as to the colors it is made of) becomes a reason to exhume JonBenet. How very, very, VERY inconvenient it would be if John and Patsy were found to have buried their daughter with a scarf whose fibers match the unidentified ones found on her skin, let alone if so much as a single drop of blood from a quick wiping were present.
Edited to clarify: I had briefly mentioned that the scarf material was not identified, then quickly saw that it was called silk. Still, we only have Patsy's word that the scarf was silk, and we know at this point that her word is nigh useless. Open questions abound. Were there red fibers in the scarf which might match the ones found on the duct tape? What material exactly are the fibers made of that are not red and were also found on the tape? Could they match the scarf?