Yes, I've noticed that there are a few expansions that are thicker than the others in CII. I think for me Japanese Temples and 1 or 2 of the others. I have most of the CII stuff, but without having it in front of me, I can't remember which ones are thicker. When I get home I'll confirm. It bugged me for a while, but I don't really pay attention to it. For me, it's only noticeable when I have a full stack of the thicker tiles right next to the regular ones. When they're all mixed up, or in the bag, I can't tell.