Are you sure the types were different? Don't think I ever got them all in the same location unless I also put some crafting ones in the mix. Some are restricted to being only offered on a battle, crafting, or gathering class, and it seems like they tend to repeat the same two or three plates over and over for each category. So unless you were changing up your job/class in order to get leves from a different category, it may not have actually been 5 unique leve plates from the same area.