So, why isn't this a thing yet?

[Canadane]

Ahem, lalafells are prey to everything. Not one person (even children) are safe from monsters, whats your point?

Lalafellen adults are still mentally and physically able to handle themselves in the dangers of the world.
It's natural to protect children until they're ready to fend for themselves. Many species do this, seemingly including the spoken races of Eorzea.