Not just frames that are stupid sizes, the 10x8, 16x20 aspect ratios of paper for darkrooms were throwbacks to plate cameras and were a complete PITA when printing from the standard 35mm film and didn't even fit medium format either, which was mostly 6x6. Then digital printing and photography came along and gave us A sizing which is fine for documents, but again doesn't fit the 3:2 aspect ratio of the now common 4:3 of small cameras.
Not a problem if you are buying cheap paper for documents, but a bit dumb when producing high quality paper for printing photographs and it's a ratio that doesn't really fit any camera.