not "fake" plates but there are some 15 and 25 pound bumper plates that are the same size as typical 45 pound plates.
at my old school, the plates were all the same size - 25, 35, and 45's.
they all were the same size as standard 45's except that they had a different color stripe in the middle.
25's were yellow, 35's were blue, and 45's were red.
unless you were up close and knew to look for it, you'd think they were all 45's.