User blog comment:FairyRaven/Fairy Tail Chapter 400: Wings of Hope, Review and Commentary/@comment-77.195.192.50-20140913110802/@comment-7418318-20140913113225

Showing the "minor" characters also shows that it isn't only the A-Team alone that's doing the fighting.

These little pictures show that it was a combined effort of the entire guild to take down Tartaros. That makes the Dark Guild appear a little more threateningly than if just the strong people went there and trashed them by themselves. Sure only the A members beat the Demon Gates, but there was an entire army of small-fry too.

It's also building suspense and as Raven said avoids that the chapter feels rushed.

And this way of showing the minor characters is certainly a lot better than the usual Bleach and Naruto thing where they all just stand around and stare at each other before the fight.

"Wwhy did Mashima create Lucy ?" "stupid key".... good thing you said you're not a Lucy hater in the other blog... could have fooled me.

Also it wasn't just a "stupid key". Apart from being a unique and priceless object just by material standards, it also is the only way that Lucy can see her longest friend and one of the last remaining mementos she has from her dead mother.