...it happens -not always by trickery. Case in point-
I bought a 1914 Polo Grounds Wagner that was already graded a 3 a few years back and have watched it deteriorate...it is as if there was moisture in the card or got in the case and I see little bits of the card peeling off and adhering to the case (maybe a bad soaker that made it through the encapsulation process before the effects became known?)
I don't have the original scan I took (only a little staining), but here is a scan from a little over 2 years ago (still wish it looked this good):
