Sure, but this question appeared to be asked form the authors POV. The author can move all that junk to the back so that the 10% has plenty of materiel. You only really need 1-2 pages tops in the front (TOC and Title Page). For fiction works you really do not need a TOC in some cases. That should leave plenty of room in the 10% for content even for a novella.
From the readers point of view... yea some authors really mess up their sample with garbage.