the concept and how it's applicate are 2 different thing. the concept are rare monster that pop randomly in the area, dropping an item that have some importance (here the bloody log and the allied seal)
in FF11 they did work on making them harder, because the game was adapted to it, here in FF14 it's not adapted to that concept, the FATE system, even if it's not perfect can be make better and was more adapted to the population of the game actual.