Forum:Has anyone else noticed something about Monsters and World maps?

Okay, so I was reading up on Awakening and I noticed that the monsters make a return appearance as enemies and the game featurea a navigable world map. So I thought to myself, 'Where have I seen that before?' The answer was, of course, Sacred Stones. Then when I clicked the link to the monster page, I found that they only appear in Gaiden, Sacred Stones and Awakening. So I looked at Gaiden and found out it was the only other Fire Emblem game with a navigable world map. So here's my question: Is the fact that world maps and monsters only appear in the same games a coincedence, or is it done on purpose?