Why do you think the characters in FF games,have such big weapons?

[farplaner]

The size of the monsters that they fight requires it.

Think about it, man. Even if you had the best sword ever, it would be wasted on a monster in comparison to which it is the size of a toothpick.
Unfortunately, that means that the FF Warriors have to learn how to use unusually large weapons as opposed to those that would be effective on humans/medium sized creatures alone.

That's flimsy. You could also say that the huge weapons are much too bulky for fighting enemies like lizards and such. It's like killing a fly with an A-Bomb. Plus, magic can be as effective (if not more so) on the big enemies as swords and such.

It's roaches that survive the A-Bomb, fool!
My position stands!

I never said anything about what survives the A-Bomb.....fool. And besides, roaches may survive the radioactive wasteland left by the bomb, but they won't survive ground zero.
Your position may stand, but your argument has flatlined, and the doctors have pronounced the time of death.